WHMCS Tutorial Guides

10 Must-Have WordPress Plugins for a Seamless eCommerce Experience     Building an eCommerce website with WordPress has never been easier, thanks to the vast... Achieving Your First MarketConnect Sale: A Step-by-Step Guide Placing MarketConnect order uses the same method as any other order within WHMCS. After the... Activating MarketConnect in WHMCS: A Step-by-Step Guide You can use MarketConnect to resell products and services to your customers via your WHMCS... Activating and Implementing Two-Factor Authentication for Admin Users: A Comprehensive Guide Activation To activate Two-Factor Authentication for a WHMCS installation, follow the... Adding New Domain Availability Checks: Expanding Your Domain Services If you want your customers to be able to check the availability of new domains, you will need... Adding an Admin User: Step-by-Step Guide For the best results, each member of your staff that will use WHMCS should have their own... Adding and Utilizing Predefined Replies: Streamlining Support in WHMCS Predefined replies let your staff quickly answer tickets about common issues. This can save... Addressing 'Invalid SASL Argument' Errors in Email Importing Symptom When you troubleshoot issues in which the system is not importing email from... Addressing 'TypeError' with str_starts_with() in Domain Management Symptom After updating to WHMCS v8.6.0, users of the ResellerClub registrar module may... Addressing 'URL May Not Contain a Query String' Issue with Microsoft: Troubleshooting Guide Symptom When configuring Microsoft® as your mail provider or for email importing, a URL... Addressing Attention Items on the System Health Status Page: Troubleshooting Guide Use the steps below to resolve some of the Needing Attention warnings in Configuration >... Addressing Post-Update Feature Issues: Troubleshooting Common Problems Symptoms After applying an update, one or more features of the WHMCS software may... Addressing Post-Update Feature Issues: Troubleshooting and Solutions Symptoms After applying an update, one or more features of the WHMCS software may cease... Addressing Post-Update Feature Problems: Troubleshooting and Solutions Symptoms After applying an update, one or more features of the WHMCS software may cease... Adjusting Records per Page Display: Customizing Pagination Settings in WHMCS You can easily change the number of results that display in lists within the Admin Area.... Adjusting Sidebar Links: Tailoring Your Website's Navigation The navigation bar links shown to visitors and clients are controlled by small snippets of code.... Adjusting Tax Rates: A Guide to Rate Modification Sales tax rates generally change over time. WHMCS allows you to manage these VAT changes... Admin Emails Showing 'Undisclosed Recipients Symptom Administrators may receive an email from the WHMCS system with two To email... Advanced Cron Troubleshooting for Intermittent Issues: Expert Solutions Symptom You may find that the cron job is not completing intermittently but does... Advanced Cron Troubleshooting: In-Depth Solutions and Strategies If you have determined that the cron job is not completing in the previous article and are... Advanced Troubleshooting for Email Piping Problems: In-Depth Solutions If an email has not been piped into the ticket system and it is not listed in the Ticket... Analyzing Automation Activity: A Comprehensive Review WHMCS includes two methods to review the status and activity of your WHMCS installation's... Assigning Custom Email Notifications to Products: A Configuration Guide You can send a custom email message whenever you create, terminate, or upgrade a service. To... Assigning Support Departments to an Admin User: A How-To Guide For an admin to view and reply to support tickets in a specific department, you must... Automated Client Data Deletion: A Guide to Streamlining the Process You may need to remove client data from your systems after they have terminated all... Billing Clients for Usage: A Guide to Usage-Based Billing WHMCS allows you to bill clients according to the resources they consume (for example... Billing Resellers per Domain: A Guide to Domain-Based Reseller Billing WHMCS allows you to vary the amount shared hosting resellers are billed based on the number... Blocking Spam Orders: Strategies for Prevention Automated bots and the spam that they create are just part of doing business online. In... Changing a Client's Currency: A Step-by-Step Guide WHMCS's multi-currency system lets clients to choose from one or more currencies. Clients can... Changing the Default Order Form Template: Customization Guide The system uses order form templates when it displays the product selection, product... Changing the Default Product Group: A Step-by-Step Customization Guide When customers visit their shopping cart (cart.php), the products in the default product... Changing the Email 'From' Address: A Guide to Customizing Sender Information All of the mail that your WHMCS installation sends will display your configured email... Changing the System Theme: Customizing WHMCS Appearance The appearance of the public and client areas are controlled by system themes. To change... Changing the WHMCS Admin Directory Name: A Step-by-Step Guide to Enhanced Security Customizing the name of your WHMCS admin directory makes it harder for bots and other... Checking for WHMCS System Requirements: Ensuring Compatibility for Seamless Operation Before you can install or update WHMCS, you must ensure that your setup meets the system... Checking for WHMCS Updates: Keeping Your System Current WHMCS automatically checks for new updates daily. When an update becomes available, a... Checking the Completion Status of Your System Cron: Verification Guide You can verify whether your system cron is running successfully from within the WHMCS... Client Area Promotions: Enhancing Customer Engagement and Loyalty Promotions for MarketConnect services are integrated directly into the every day user... Completing the WHMCS Setup Wizard: A Step-by-Step Walkthrough The first time that you log in to the Admin Area, the Getting Started Wizard (or Setup... Configuring Amazon S3 Storage in WHMCS: A Comprehensive Setup Guide You can use Amazon S3™ as your storage provider in WHMCS. Before you can set this up... Configuring Amazon S3™ Bucket for WHMCS: A Step-by-Step Setup Guide If you want to use Amazon S3™ as the storage provider for your WHMCS installation, you... Configuring Application Links with cPanel: Step-by-Step Setup Application Links allows customers to seamlessly transition from cPanel to WHMCS using... Configuring Domain Display Options in the Ordering Process: WHMCS Customization Guide You can customize the domain options that display to customers during the ordering process.... Configuring Domain Extensions (TLDs): A Comprehensive Setup Guide If you want to sell domain registrations with WHMCS, you will need to configure the domain... Configuring Domain Redemption Fees: A Guide to Fee Customization Domain redemption fees add an automated charge to renew expired domains during the domain... Configuring Email Piping: A Step-by-Step Guide for Streamlined Communication Email piping allows customers to send email to your support department email addresses. The... Configuring Google as Your Mail Service Provider: A Step-by-Step Guide WHMCS can send emails without any additional configuration using PHP mail(). While this... Configuring Invoice Settings: A Step-by-Step Guide You can configure when and how WHMCS invoices your customers.  Configure Invoice... Configuring Microsoft as Your Mail Service Provider: A Step-by-Step Guide WHMCS can send emails without any additional configuration usingPHP mail(). While this... Configuring Payment Capture Settings: A Step-by-Step Guide WHMCS can automatically charge your customers' payment methods. This removes the need to run... Configuring Payment Reminders: A Guide to Reminder Settings WHMCS can send payment reminders to your customers in advance of their payment dates. This... Configuring Product Group Features: A Step-by-Step Guide For some order form templates, you can configure product group features display details... Configuring SMTP in WHMCS 8+: A Step-by-Step Guide WHMCS can send emails without any additional configuration using PHP mail(). However,... Configuring Support Departments: A Step-by-Step Setup Guide WHMCS includes a fully-featured support system. To use this system, you will need to... Configuring WHMCS Cron Jobs: Step-by-Step Setup Guide You will need to configure the cron job as soon as you finish installing WHMCS. The cron... Configuring WHMCS to Use Alternative Mail Providers: A Comprehensive Guide WHMCS comes with the ability to send emails without any additional configuration using... Configuring Your Domain Registrar: A Step-by-Step Guide To sell domains with WHMCS, you will need to set up at a domain registrar. WHMCS supports... Configuring Your First Non-cPanel, Plesk, or DirectAdmin Server: A Step-by-Step Guide Before you can sell and provision hosting accounts, you must add at least one server to... Configuring Your First Payment Gateway: A Step-by-Step Guide Setting up a payment gateway is a crucial step in configuring your WHMCS installation. If... Configuring a Lookup Provider: A Step-by-Step Guide To allow your customers to search for and find the domains they want to buy, you must... Configuring a Personalized Invoice Number Format: Step-by-Step Customization Each invoice includes a numerical identifier (the invoice number). You can choose to use the... Configuring cPanel Site Software for WHMCS Integration: A How-To Guide You can install WHMCS using cPanel's Site Software feature. Before you can perform the... Configuring the ResellerClub Registrar: A Step-by-Step Setup Guide Domain registration is an easy product offering to increase your revenue. WHMCS automates... Configuring the Temporary Update Path in WHMCS: A Step-by-Step Guide When you update WHMCS, the temporary path allows the system to stage files. You... Configuring the Update Maintenance Message: Communicating Changes Effectively You can easily set a message that will display to other admins and users whenever an update... Configuring the WHMCS Update Channel: Tailoring Update Preferences The Update Channel that you select provides control over which update notifications you... Configuring the eNom Lookup Provider: A Step-by-Step Setup Guide To allow your customers to search for and find the domains they want to buy, you must... Configuring the eNom Registrar: A Step-by-Step Setup Guide Domain registration is an easy product offering to increase your revenue. WHMCS automates... Confirming the Invocation of Your System Cron: Verification Guide Verify that the System Cron is being called To ensure that the daily automation tasks... Creating Your First Knowledgebase Article: A Step-by-Step Guide You can easily set up a knowledgebase to help your customers find answers to common... Creating Your First VPS/Dedicated Server Product: Step-by-Step Setup Guide To sell something using WHMCS, you need to configure a product. Server/VPS products... Creating Your First WP Squared Product: A Step-by-Step Tutorial To sell something using WHMCS, you need to configure a product. The steps below create a... Creating Your First cPanel Server: A Step-by-Step Tutorial Before you can sell and provision hosting accounts, you must add at least one server to... Creating Your Inaugural Product Group: A Setup Guide The first step to creating products is setting up a product group. Product groups are... Creating an HMRC Application for UK VAT: A Step-by-Step Guide This process is only necessary in some releases of WHMCS 8.1 and earlier. The UK... Custom Ticket Status Language Display in WHMCS Symptom After updating to WHMCS 8.7.2, admins may encounter a problem with the display... Customizing Date Display Formats: A Guide to Personalizing Date Presentation WHMCS can display dates in several different formats, and you can configure display for... Customizing Domain Categories: Tailoring Your Domain Portfolio Domain categories group domain TLDs into categories on the domain registration page... Customizing Page URL Formatting: A Guide to Adapt Your WHMCS Website WHMCS can create search engine-friendly URLs for some public-facing pages. Note:... Customizing System Themes: Crafting Unique Layouts and Designs A system theme in WHMCS controls the client facing user interface. WHMCS allows you to provide a... Customizing WordPress Themes: A Beginner’s Guide to Child Themes and CSS Tweaks     WordPress is one of the most popular content management systems (CMS) in the world, largely... Customizing the Logo Image in the Client Area: Tailoring Your Branding You can easily change the logo image that displays in emails, on generated invoices, and... Customizing the Logo Image: Personalizing Your WHMCS Branding You can easily change the logo image that displays in emails, on generated invoices, and... Customizing the WHMCS Cron Schedule: Configuration Guide The WHMCS cron job performs many of the automated tasks for your WHMCS installation. You... Dealing with Lost Two-Factor Authentication Tokens: Recovery Steps If you do not have access to your Two Factor Authentication token (eg. lost phone or new... Depositing Funds: A User-Friendly Guide Before you can deposit funds to MarketConnect, make certain that you have already completed... Disabling MySQL Strict Mode: A Guide to Configuration You must disable MySQL® Strict Mode in order to run WHMCS on your server. We recommend... Disabling Quick Shortcuts in cPanel and Plesk Services: A Step-by-Step Guide The Client Area displays a Quick Shortcuts section in the product details for services that... Disabling System Notification Emails for Admin Users: Step-by-Step Instructions WHMCS sends notification emails to admins for relevant system events, self-diagnosis of... Disabling an Admin User Account: A Step-by-Step Guide You can disable an admin, preventing them from logging in to the Admin Area. This will... Effective Promotion Management: Strategies and Tips This guide assumes you have already completed MarketConnect activation for at least one... Efficient Service Management: Best Practices and Tips MarketConnect orders appear in the Orders list in the Admin Area. All MarketConnect... Effortless WHMCS Installation Using cPanel Site Software: A Step-by-Step Tutorial You can install WHMCS easily using cPanel's Site Software feature. To do this: 1. If... Eliminating Legacy Smarty Tags in WHMCS 8.7+: A Migration Guide In previous WHMCS versions, Smarty 3's SmartyBC provided backwards compatibility for... Enabling Domain Renewal Orders in the Client Area: A WHMCS Configuration Guide You can enable and disable clients' ability to place domain renewal orders from within... Enabling Page Language Selection for Visitors: Enhancing User Experience WHMCS includes multiple Client Area and store translations through files in the lang... Enabling SSL for Your WHMCS Installation: A Secure Setup Guide WHMCS often contains private and sensitive data that passes between WHMCS and end users'... Enabling Secure MySQL Connections: A Guide to Encrypted Communication To use WHMCS with an encrypted MySQL® connection, you will need to perform additional steps... Enabling Two-Factor Authentication: A Step-by-Step Guide Two-Factor Authentication adds a layer of security by adding a second step to the login... Enabling Users to Remove Saved Payment Cards: A User-Friendly Guide By default, WHMCS allows users to add and update credit and debit card details (their... Enforcing a Password Reset: Step-by-Step Instructions In some circumstances, you may need to force a user to reset their password before they... Enhancing Security with Two-Factor Authentication for Clients: A Guide Once a Two-Factor Authentication service has been activated for clients, the following... Enhancing Security with Two-Factor Authentication for Staff: A Guide Once a two factor authentication service has been activated for staff, the following... Enhancing Security: Restricting Access by IP Address for Improved Control For increased protection, if your staff uses fixed IP addresses, you can restrict access to a... Enhancing WHMCS Security: Additional Measures for a Safer Installation Your WHMCS installation will store sensitive information for your customers and for your... Establishing Your Debut Reseller Hosting Product: A Setup Tutorial To sell something using WHMCS, you must configure a product.  Reseller Hosting products... Establishing a Development and Testing Environment: Step-by-Step Setup Guide Creating a testing and development environment will let you verify all of your customizations... Establishing a Universal Email Signature: Streamlining Your Communication You can specify the default signature applied to all outgoing Email Templates sent from... Expanding Your Sales Reach: Selling in Multiple Currencies Made Easy WHMCS lets you sell a single product in multiple currencies. You can set the product price in... Exporting Client Data: A Guide to Data Extraction A client may request a copy of the data you keep about them. WHMCS facilitates this via a... Fixing 'Call to undefined method Mailbox::getRawHeader()' Error in Email Importing Symptom After updating to WHMCS 8.6.0, users may encounter a Call to undefined method... Fixing 'Maximum Execution Time Exceeded' in /path/to/whmcs/vendor/tecnickcom/tcpdf/tcpdf.php Symptom When generating a PDF invoice or quote (for example, during the daily automation... Fixing 'TypeError' in WHMCS\File::guessFileExtension() Function Symptom A TypeError referencing the guessFileExtension function appears in your PHP... Fixing 'Undefined Constant' Error in Monthly Orders Report Symptom After updating to WHMCS 8.6.1, you may experience an Undefined Constant error when... Fixing Failed Hosting Account Creation: Troubleshooting Guide When an automated module action fails, it is added to the Module Queue. Events that can... Fixing Missing Credit Card Fields During Checkout: Troubleshooting Guide Symptom After applying the 8.3.0 update, the Credit Card Number, Expiry Date, and CVV... Fixing Problems with One or More Features After an Update: Troubleshooting Guide Symptoms After applying an update, one or more features of the WHMCS software may... Fixing v8.3 Update Absence: Troubleshooting the Missing Upgrade Symptom After navigating to Utilities > Update WHMCS  and clicking Check for Updates,... Fortifying the Configuration File: Essential Steps for Improved Security We recommend adjusting the permissions for the configuration.php file in your WHMCS root... Generating Early Renewal Invoices: A Step-by-Step Process There may be times where a client asks for you to invoice them for the next renewal date... Generating Individual Renewal Invoices for Client Services: A Step-by-Step Tutorial By default, WHMCS groups service renewal invoices that are due on the same day into a... Getting Started with WHMCS: A Beginner's Guide After you complete installation, we recommend completing your configuration by setting up the... Identifying the Problem with Automatic Update Failures: Troubleshooting Guide You attempted to perform an automatic update but it failed and showed an error message... Identifying the Timezone Used in Command Line and Cron Engine: A Step-by-Step Guide Many server configurations utilize a separate php.ini file in the command line or cron... Identifying the php.ini Used for Command Line and Cron Engine: A Step-by-Step Guide Many server configurations utilize a separate php.ini file in the command line or cron... Initiating Your Initial Shared Hosting Product: A Creation Guide To sell something using WHMCS, you need to configure a product.  Shared Hosting products... Leveraging WHMCS for GDPR Compliance: Key Features and Benefits The General Data Protection Regulation (GDPR) is Europe's big new data privacy law. It comes... Linking to the Shopping Cart and Client Area: Simplifying User Navigation WHMCS allows you to link directly to the shopping cart, to specific product groups, or to... Locating the 'Reset & Send Password' Option: A Step-by-Step Guide In v7.x and earlier, a Reset & Send Password option was located in the Clients... Logging In to the WHMCS Admin Area: Step-by-Step Guide The WHMCS Admin Area lets you configure WHMCS, manage orders, work with clients and their... Managing Lost Backup Codes: Steps for Recovery If you have lost both your two factor token (ie. phone) and the backup code, this article... Managing Pending Orders: A Comprehensive Guide With WHMCS all orders are pending until accepted. Orders can reviewed by navigating to Orders... Mandating Two-Factor Authentication for Clients and Admins: A Configuration Guide After a two factor authentication service has been activated,  clients or admins can be... Mandatory Marketing Email Opt-In for Clients: Implementing in WHMCS You may want or need to offer clients the ability to opt in and out of the marketing... Manual Browser-Based WHMCS Update: Step-by-Step Instructions We recommend using the Automatic Updater utility to apply updates, but you can also apply... Manual Command Line WHMCS Update: Step-by-Step Procedure When a new version of WHMCS is available, in-product notices will appear. We recommend using... Manually Adding a Client: A Step-by-Step Guide This guide shows how to manually add a client account to WHMCS. For example, you may do... Maximizing Sales with Shopping Cart Promotions: Strategies and Implementation Enabled MarketConnect services will be made available to customers during the ordering... Migrating Away from Legacy Smarty Tags in WHMCS Symptom After updating to WHMCS 8.7, admins may see a Legacy Smarty Tags warning in... Migrating Clients to Another cPanel Server (cPanel to cPanel): Step-by-Step Guide After moving hosting accounts from a cPanel & WHM® server to a new one, you may be... Migrating from Universal Analytics to Google Analytics 4: Transition Guide Introduction Google® will discontinue their Universal Analytics service on July 1, 2023.... Migrating from an External Mail Provider to PHP Mail in WHMCS Symptom After updating to WHMCS 8.6.1, you may be unable to select PHP Mail for Mail... Migrating to Amazon S3 from Local File Storage: A Step-by-Step Guide Before you perform the steps below, complete the steps in Configuring an Amazon S3 Storage... Modifying Navigation Bar Links: Tailoring Your Website's Menu The navigation bar links shown to visitors and clients are controlled by small snippets of code.... Modifying Payment Instructions on Invoices: A How-To Guide The Mail in Payment or Bank Transfer payment gateway modules display payment instructions... Modifying the Pay-To Address on Invoices: A Step-by-Step Guide The invoices that WHMCS generates include an address to which your customers can remit... Navigating the SagePay Tokens Deprecation and Transition to SagePay Tokens v2 Opayo (formerly Sage Pay) has announced changes to their SCA and 3DSv2 API... Navigating the Weebly Purchase Flow: A User Guide Visitors to your website can purchase Weebly's website builder as a standalone product... Notification: Discontinuation of Validation.com Services Validation.com has announced that they are discontinuing service on April 9, 2023. After... Optimizing Your Website with WordPress Hosting Services In WHMCS 8.3 and later, you can easily offer automated WordPress hosting for your clients. They... PayPal Checkout SSL Requirement: Ensuring Secure Transactions The PayPal Checkout payment gateway module requires an HTTPS-secured connection to create the... Personalizing Email Content: Tailoring Your Messages The email templates allow you to customise the messages that go out to  your customers when... Personalizing Oops! Error Pages: Enhancing Visuals and Branding An Oops! message displays in WHMCS 7.2 and above when a catchable error occurs:... Preparing for GDPR Compliance: A Comprehensive Guide The General Data Protection Regulation (GDPR for short) is Europe's big  new data privacy... Preparing to Update WHMCS: Essential Steps for a Smooth Upgrade To avoid problems when updating WHMCS, you will need to take some preparatory steps to ensure... Product Name and Description Translation: Expanding Your Market Reach You can translate product names and descriptions into multiple languages using the... Receiving BCC Copies of All WHMCS Emails: A Configuration Guide You can easily configure WHMCS to send you a BCC copy of all of the email your WHMCS... Refreshing Admin Dashboard Widgets: Step-by-Step Guide For the admin homepage to load as quickly as possible, the contents of the admin... Relocating the Cron Directory: A Guide to Efficient Cron Management We recommend moving the crons directory to a private directory above your web root. This will... Replacing Legacy Smarty Tags with Hooks: A Migration Guide In previous WHMCS versions, Smarty 3's SmartyBC provided backwards compatibility for... Requiring Clients to Accept Terms and Conditions: A Guide to Policy Compliance You may want to require a client to indicate that they have read and agree to your terms and... Resolving 'Apply Update Dry-Run Permission Issues' Error: A Step-by-Step Guide Introduction An Apply update dry-run detected x permission issues error, where x is... Resolving 'Bad Request' Error When Importing Microsoft® Email: Troubleshooting Guide Symptom WHMCS fails to import emails using a Microsoft email service (for example,... Resolving 'Base Table or View Not Found' Error: Troubleshooting Guide Introduction This guide demonstrates how to resolve a Base table or view not found... Resolving 'Connection Unsuccessful' Error with Microsoft: Troubleshooting Guide Symptom When configuring Microsoft® as your mail provider or for email importing, a... Resolving 'Down for Maintenance' Error: Troubleshooting and Solutions After performing an update, a Down for Maintenance (Err 2) or (Err3) error may occur when... Resolving 'GoCardless Oops' Error During Mandate Creation: Troubleshooting and Solutions Symptom Clients attempting to create new mandates via the GoCardless payment gateway... Resolving 'Integrity Constraint Violation: 1062 Duplicate Entry' Error in tblinvoices Table Symptom Performing an action that creates an invoice (including the daily automation cron... Resolving 'Invalid CSRF Protection Token' Error When Creating Billable Items in WHMCS Symptom After updating to WHMCS 8.7.1, admins may encounter an Invalid CSRF Protection... Resolving 'No Input File Specified' Error: Troubleshooting Guide Symptom Admins receive an email from your server's cron daemon every five minutes with the... Resolving 'POP3 Read Failed - Connection Closed?' Errors: Troubleshooting Guide Symptom You may receive a POP3 connection error email stating that One or more POP3... Resolving 'Product Attribute Package Name XXX Not Found on Server' Issue This article explains how to troubleshoot the cPanel Product attribute Package Name XXX not... Resolving 'Single ID Not Found in Response' Errors: Troubleshooting Guide Symptom You may receive a POP3 connection error email stating that One or  more POP3... Resolving 'TypeError' Issue in Client's Email Tab Symptom After updating to WHMCS 8.6.1, you may see a TypeError error when you access the... Resolving 'TypeError' While Sending Email Marketer Rules Symptom After updating to WHMCS 8.6.1, you may see a TypeError error when sending Email... Resolving 'Unable to Add Products to Cart' Issues: Troubleshooting Guide Symptom Clicking Order Now on the shopping cart product selection page (cart.php) or... Resolving 'Unable to Perform Automatic Updates': Troubleshooting Guide If Update Now is disabled in the Automatic Updater utility at Utilities > Update WHMCS, an... Resolving 'WHMCS Pop Cron Did Not Run' Email Notification Issue A warning email is sent to full administrators if the POP3 Import Method feature to... Resolving Certificate Authority Verified SSL Certificate Detection Issues on example.com Symptom You may see the following error message: Website SSL A Certificate... Resolving Client Area Navigation and Sidebar Titles Not Displaying: Troubleshooting Guide Symptom The primary navigation bar and sidebar menu items do not display correctly.... Resolving Communication Error with Server: Troubleshooting Guide An error stating An error occurred while communicating with the server. Please try again... Resolving Cron Stuck on 'Executing System Queue' Step: Troubleshooting Guide Symptom During the daily automation cron run, the script takes a long time to... Resolving Daily Cron Not Executing at the Expected Hour: Troubleshooting Guide Symptom You receive the following WHMCS Daily System Cron Attention Needed email:... Resolving Fatal Error: Class 'Laminas\ZendFrameworkBridge\Autoloader' Not Found Symptom After switching to PHP 8.1, you may see a Class not found error when accessing the... Resolving High Memory Usage in Client Service Lists: Troubleshooting Guide Symptom After applying the 8.3.0 update, you may see high memory usage or a... Resolving Inconsistent Timestamps in Support Ticket Messages: Troubleshooting Guide Symptom Support ticket messages that you imported using email importing or email piping... Resolving Invalid Value 'paper_lantern' for 'cpmod' Setting Symptom When provisioning a new cPanel hosting account, the process fails with a... Resolving MySQL Error Code 1142 - 'Command Denied to User Symptom When applying an update to WHMCS, a Command denied to user error displays. For... Resolving MySQL Error Code 1146 - 'Base Table or View Not Found Introduction When applying an update to the WHMCS software an error stating  Base... Resolving Permission Issues in Update Dry-Run: Troubleshooting Guide Introduction An Apply update dry-run detected x permission issues error, where x is the... Resolving TypeError: Argument 3 in WHMCS\Domains\AdditionalFields::processFieldOverrides() Symptom When viewing a domain registration in the Admin Area or Client Area, you may... Resolving a 'Down for Maintenance' Error: Troubleshooting Guide After performing an update, a Down for Maintenance (Err 2) or (Err3) error may occur when... Resolving a 'Down for Maintenance' Message: Troubleshooting Guide After performing an update, a Down for Maintenance (Err 2) or (Err 3) error may occur when... Resolving a Cron Invocation Frequency Warning: Troubleshooting Guide To automate tasks, WHMCS requires the regular and frequent invocation of a file via cron.... Resolving a Daily Cron Run Warning: Troubleshooting Guide WHMCS performs a number of tasks once per day, such as processing payments, generating... Resolving a TypeError in License.php: Troubleshooting and Solutions Symptom After applying the 8.2.0 update, you may occasionally observe a TypeError error... Resolving ionCube Loader Error: File Cannot Be Decoded (Type [1/72]) Symptom After switching to PHP 8.1, you may see an ionCube Loader® error when accessing... Resolving the 'Column 'group_id' Cannot Be Null' Error: Troubleshooting Guide Symptom When you update to WHMCS 8.3, you may see the following Integrity constraint... Resolving the 'Down for Maintenance' Error: Troubleshooting and Solutions After performing an update, a Down for Maintenance (Err 2) or (Err3) error may occur when... Resolving the 'WHMCS\Config\Setting' Error: Troubleshooting Update Issues Symptom After applying the 8.3.0 update, you may observe the following GuardedForUpdate... Restoring Default Email Templates: A Step-by-Step Guide Introduction This guide demonstrates how to restore the Default Email Templates... Restoring and Safeguarding Customer Invoice Data: Best Practices In some jurisdictions, you may need to fix the client's name, address, and tax ID to the... Reviewing Email Marketing Consent History: A Comprehensive Guide Version 7.5 introduced logging each time a client opts in or out from marketing emails.... Securing Writable Directories: Best Practices for Enhanced File Safety We recommend moving all writeable directories to a private location in order to prevent... Selecting Additional Product Features: A Guide to Customization You can customize your products to allow customers to enter values during the order process,... Selling MarketConnect Products: Strategies and Implementation You can use MarketConnect to resell products and services to your customers via your WHMCS... Service Cancellation by Administrators: A Step-by-Step Guide Whilst WHMCS can provide self-service cancellations for clients, staff members can also... Setting Default Country and Language Preferences: A Configuration Guide You can configure a default country and language for your WHMCS installation. Set... Setting Default Nameservers for Domain Registration Orders in WHMCS You can specify the default nameservers that the system uses when clients place an order... Setting Up Cross-Selling Recommendations: A Guide to Boosting Sales Cross-selling allows you to display product recommendations to your customers while they... Setting Up Email Importing via Microsoft: Simplified Communication Integration WHMCS can import email through several different service providers, including POP3 or... Setting Up Email Piping with cPanel: Streamlining Ticket Creation In WHMCS, navigate to Setup > Support > Support Departments Note down... Setting Up Microsoft 365® as Your Mail Service Provider: A Step-by-Step Guide WHMCS can send emails without any additional configuration using PHP mail(). While this works... Setting Up On-Demand Renewals: A Configuration Guide WHMCS 8.8 introduced on-demand renewals for existing services, allowing clients to renew... Setting Up POP3 Importing with OAuth via Google: Seamless Email Integration WHMCS can import email through several different service providers, including POP3 or... Setting Up SMTP in WHMCS 7: A Configuration Guide WHMCS comes with the ability to send email without any additional configuration using the... Setting Up WordPress Hosting: Configuration Guide In WHMCS 8.3 and later, you can easily offer automated WordPress hosting for your... Setting Up Your First DirectAdmin Server: A Step-by-Step Tutorial Before you can sell and provision hosting accounts, you must add at least one server to... Setting Up Your First Non-Hosting Product: A Step-by-Step Tutorial To sell something using WHMCS, you need to configure a product. Other (non-hosting)... Setting Up Your First Plesk Server: A Step-by-Step Tutorial Before you can sell and provision hosting accounts, you must add at least one server to... Setting Up Your First Product: A Beginner's Guide To sell something using WHMCS, you must set up and configure a product: Shared... Setting Up Your First WP Squared Server: A Step-by-Step Tutorial Before you can sell and provision hosting accounts, you must add at least one server to... Setting Up an Admin Avatar for the Staff Online Widget: Configuration Guide Admin users can add a custom avatar above their names in the Staff Online widget in the... Shopping Cart Promotions Not Displaying: Troubleshooting Guide Symptom MarketConnect service promotions do not automatically display during the order... Step-by-Step Guide to Installing WHMCS To start using WHMCS, you will need to install it on your server. You may need help from your... Store Purchase and Upsell Promotions: Boosting Sales Strategies All MarketConnect services come with ready made landing pages to help you promote them.... Streamlining Product Price Management: Automation for Seamless Updates WHMCS can automatically retrieve currency exchange rates and update product prices on a... Stripe and Reserve Bank of India (RBI) Regulatory Compliance: Important Notices and Warnings Stripe customers in certain locations may receive an email from Stripe with the following... Stripping Quoted Emails from Tickets: Enhancing Ticket Clarity Introduction Emails piped into the support ticket system can sometimes be cluttered by... Switching Your Default Currency: A Guide to Currency Configuration WHMCS's multi-currency system lets clients choose from one or more currencies. On a new WHMCS... Tagging a Staff Member in a Note: Collaborative Notes in WHMCS In version 7.5 and above, members of staff can be mentioned when writing an internal note on... Tailoring Affiliate Link Destinations: Personalizing Your Affiliate Marketing Strategy When a visitor clicks on an affiliate's link, the system redirect them to the URL that you... Tailoring Text: Personalization and Customization Steps for customising the text displayed in WHMCS are as follows: 1. Open the... Tailoring Your Pricing Structure: A Guide to Customization This guide assumes you have already completed MarketConnect activation for at least one... Template Preview: A Guide to Reviewing Your Design When developing a new template it is often desirable to preview it yourself whilst other... Text Customization and Translation: Tailoring Content to Your Needs WHMCS supports over 25 different languages with the ability to add more to your... Troubleshooting 'A Fatal Error Occurred While Fetching the Update' Error: A Step-by-Step Guide An error stating A fatal error occurred while fetching the update may occur in the Automatic... Troubleshooting 'An Unknown Error Occurred': A Comprehensive Guide Sometimes a third party system or module will provide a response that WHMCS is unable to... Troubleshooting 'Apply Update Dry-Run Permission Issues' Error: A Comprehensive Guide Introduction An Apply update dry-run detected x permission issues error, where x is... Troubleshooting 'Apply Update Dry-Run Permission Issues' Error: A Step-by-Step Guide Symptom An Apply update dry-run detected x permission issues error, where x is the... Troubleshooting 'Apply Update Dry-Run Permission' Error: Solutions and Steps Introduction An Apply update dry-run detected x permission issues error, where x is the... Troubleshooting 'Argument 1 Must Be an Instance of PDOStatement' Error Symptom When performing MySQL®-intensive actions, you may see the following errors:... Troubleshooting 'Argument 7 Passed to processPoppedTicket()' Error: A Comprehensive Guide Symptom After performing a WHMCS software update, emails that the system imported to... Troubleshooting 'Cannot Connect to Host (php_network_getaddresses: getaddrinfo Failed: Name or Service Not Known)' Error: A Comprehensive Guide Symptom Admins may see a POP3 Connection Error report email stating that one or more... Troubleshooting 'Cannot Connect to Host' Error: Resolving php_network_getaddresses Error Symptom Admins may see a POP3 Connection Error report email stating that one or more POP3... Troubleshooting 'Cannot Select INBOX, Is This a Valid Transport?' Error Admins may encounter the following error when configuring support department mail... Troubleshooting 'Check for Updates Failed' Error: A Comprehensive Guide You may encounter a Check for Updates Failed error in Configuration > System... Troubleshooting 'Class Not Found' Error in TransIP: Solutions and Steps Symptom After updating to WHMCS 8.5.1, users attempting to configure the TransIP registrar... Troubleshooting 'Column Not Found' Error (Error 1054) in MySQL: Solutions and Steps Symptom After updating to WHMCS 8.5.1, admins attempting to create or edit products may... Troubleshooting 'Declaration of WHMCS\View\Menu\Item::setLabel($label)' Error: A Comprehensive Guide Symptom After updating to WHMCS 8.4.0, you may observe the following setLabel error:... Troubleshooting 'Down for Maintenance' Errors: Getting Your Website Back Online After performing an update, a Down for Maintenance (Err 2) or (Err3) error may occur when... Troubleshooting 'Duplicate Entry '0' for Key 'PRIMARY' Error: Step-by-Step Guide Symptom You may encounter the following error after copying a MySQL database... Troubleshooting 'Exception Thrown in Jobs Queue Execution' Error: A Step-by-Step Guide Symptom After updating to WHMCS 8.4.0, you may observe one of the following Exception... Troubleshooting 'Failed Communication with Update Server' Error: Step-by-Step Guide You may encounter a Network Issue - Failed Communication with Update Server error when... Troubleshooting 'Failed Opening Required File' Error: A Comprehensive Guide" Symptom When accessing parts of WHMCS, you may see the following Oops error:... Troubleshooting 'Failed to Load Module WpToolkitCli' Error at Module Command Symptom When provisioning WordPress® hosting with the cPanel server module, you may... Troubleshooting 'Failed to Remove Legacy Modules' Error: Solutions and Fixes Symptom After you update WHMCS, you may encounter the following message in an email or... Troubleshooting 'File Could Not Be Downloaded' Error: A Step-by-Step Guide Symptom The Automatic Updater utility may fail on certain server configurations and... Troubleshooting 'General Error: 3988 Conversion from Collation utf8mb3_unicode_ci into latin1_swedish_ci Impossible for Parameter Symptom Admins receive a POP3 Connection Error email with a Error: SQLSTATE[HY000]:... Troubleshooting 'Impossible to Create the Root Directory' Errors: A Comprehensive Guide Symptoms An Oops error page may occur when sending an email via WHMCS or accessing the... Troubleshooting 'Insecure Connection Notice' in Admin Area Access Symptom When accessing the WHMCS Admin Area, the following message displays at the top of... Troubleshooting 'InvalidArgumentException: Query String Must Not Include a URI Fragment' Error Symptom You have enabled the Log Errors setting and see a InvalidArgumentException error... Troubleshooting 'Logon Failure: Unknown User Name or Bad Password' Error: A Step-by-Step Guide Admins may encounter the following error when configuring support department mail... Troubleshooting 'Module Not Found' Error: A Step-by-Step Guide Symptom When performing an action which involves invoices or transactions (such as placing... Troubleshooting 'No Nameservers are Defined for the Server This Domain is Assigned to' Error: A Step-by-Step Guide Symptom When attempting to register or transfer a domain name, you may encounter a No... Troubleshooting 'Order Not Found...Exiting...' Error: Step-by-Step Guide The error message Order not found.. Exiting... may be encountered when placing a new... Troubleshooting 'PHP Fatal Error: Class Not Found' Error: A Comprehensive Guide Encountering an error similar to that shown below indicates a core WHMCS file is missing:... Troubleshooting 'Remote Transaction Failure - Please Contact Support' Error: A Comprehensive Guide Symptom A Remote Transaction Failure. Please Contact Support. error may display to clients... Troubleshooting 'SMTP connect() Failed' Error with External SMTP Mail Providers: A Step-by-Step Guide Symptom When sending emails using an external SMTP mail provider (including Gmail™), a... Troubleshooting 'Service Not Found' Error During Domain Move: A Comprehensive Guide Symptom After updating to WHMCS 8.4.0, you may observe the following error when... Troubleshooting 'The File /path/to/whmcs/index.php Is Corrupted' Error: Solutions and Fixes Symptom When installing, upgrading or using WHMCS, you encounter the following error,... Troubleshooting 'The Template Could Not Be Found' Error: A Step-by-Step Guide Symptom When accessing certain pages in WHMCS, you may encounter the following error,... Troubleshooting 'This Payment Solution Module Could Not Be Loaded' Error: A Step-by-Step Guide Symptom When viewing the Manage Existing Gateways tab at Configuration > System... Troubleshooting 'TypeError' in ProcessCreditCardPayments Task with Stripe Symptom After updating to WHMCS 8.6.1, you may experience a TypeError error when the... Troubleshooting 'TypeError: Argument 1 Passed to Carbon\CarbonInterval::setLocalTranslator()' Error Symptom You may encounter the following error after updating through WHMCS v8.0:... Troubleshooting 'TypeError: Argument 1 Passed to _stripe_isNoDecimalCurrency()' Error: A Comprehensive Guide Symptom After updating to WHMCS 8.4.0, installations using the Stripe Payment Gateway... Troubleshooting 'TypeError: Return Value of convertIniSize() Must Be of the Type int' Error Symptom When accessing support tickets or areas of WHMCS with file attachments, you... Troubleshooting 'Update Message Validation Issue' Error: Solutions and Fixes Symptom An Update Message Validation Issue notice may display at Utilities > Update... Troubleshooting 'WHMCS\Module\Mail\SmtpOauth' Missing in Google Mail OAuth Integration Symptom After updating to WHMCS v8.6.0, users of the Google Mail Provider using the... Troubleshooting 'Your License Key is Invalid' API Errors: A Comprehensive Guide Symptom When using the WHMCS API, you may the following error:... Troubleshooting '_getSSORedirectUrl() must be of the type string, null given' Error Symptom When clicking Login to Control Panel for a Plesk service, you may encounter... Troubleshooting 'cURL Error 28: Operation Timed Out' Error: Solutions and Fixes Symptom You may see a cURL error 28: Operation timed out error when you use the Automatic... Troubleshooting 'sslv3 alert handshake failure' and 'tlsv1 alert protocol version' Errors: A Step-by-Step Guide Symptom cURL Error code 35 Unknown SSL protocol, Unsupported SSL protocol, sslv3 alert... Troubleshooting Accented Character Display in CSV Reports: A Step-by-Step Guide Symptom Opening a CSV export report using Microsoft® Excel can cause accented characters... Troubleshooting Admin Directory Errors: A Comprehensive Guide Symptom WHMCS displays one of the error messages below when it detects a conflict... Troubleshooting Administrators Not Receiving Support Ticket Notifications: A Step-by-Step Guide If you have configured support departments, admins, and admin roles but admins are not... Troubleshooting Backup Errors: A Comprehensive Guide A number of errors may appear when clicking the Test Connection button on the Setup >... Troubleshooting Blank Page and 'Oops' Error Messages: A Step-by-Step Guide Via The Admin Area Navigate to Configuration > System Settings > General... Troubleshooting Blank Page and 'Oops' Error Messages: Resolving Website Issues Via The Admin Area To troubleshoot a blank page or Oops error message, navigate to... Troubleshooting Blank Page and 'Oops' Error Messages: Step-by-Step Guide Via The Admin Area To troubleshoot a blank page or Oops error message, navigate to... Troubleshooting CURL Error 56 - OpenSSL SSL_read Unexpected EOF: Solutions and Fixes Symptom You may see the following error when attempting to perform actions on remote... Troubleshooting CURL Error 56 - OpenSSL SSL_read: Success Symptom You may encounter the following error when attempting to perform actions like... Troubleshooting Chrome Browser Crashes with 2Checkout Inline Checkout: A Step-by-Step Guide Symptom Chrome™ browsers may crash when your customer makes a payment using 2Checkout.... Troubleshooting Client Area Homepage Panel Display Issues: Solutions and Tips Symptom After updating to WHMCS 8.5.0, client accounts with four or more services may see... Troubleshooting Client Details Display Issues on Invoices: A Step-by-Step Guide Sometimes client details may not be displayed on an invoice the way you're expecting.... Troubleshooting Client Logs Displaying Server IP Address: A Comprehensive Guide Symptoms When viewing the activity logs kept by WHMCS, the final column indicates the IP... Troubleshooting Critical Error - 'Could Not Connect to the Database Symptom After applying the 3rd November 2020 MariaDB updates  we have received reports... Troubleshooting Cron Halting on Tenant Usage Metrics: A Comprehensive Guide Symptom During the daily automation cron run, the script requires a long amount of... Troubleshooting Cross-selling Recommendations Not Displaying on Order Form Symptom You have configured cross-selling for a product, but the cross-sells... Troubleshooting Domain Availability Problems: A Step-by-Step Guide Domain results can sometimes be reported inaccurately. For example a domain showing available... Troubleshooting Domain Invoice Generation: A Comprehensive Guide You may encounter a problem in which the system does not generate an invoice for a domain... Troubleshooting Domain Provisioning Problems: A Comprehensive Guide WHMCS can automatically register/transfer domains, you can specify whether this happens... Troubleshooting Domain Renewal Problems: A Step-by-Step Guide You may experience problems when renewing domains. Consider the sections below to begin... Troubleshooting Email Piping Problems: A Comprehensive Guide If an email has not been piped into the ticket system, the first reference point is... Troubleshooting Email Sending Issues in WHMCS 7.x: A Comprehensive Guide This article is for WHMCS 7.x. If emails are not being sent by your WHMCS installation... Troubleshooting Email Sending Problems: A Comprehensive Guide The steps below will troubleshoot issues in WHMCS 8.0 and higher. For help troubleshooting... Troubleshooting Empty Invoices and Duplicated Reminder Emails: A Comprehensive Guide Symptoms The system automation tasks are generating two invoices for each client: one... Troubleshooting Empty Page Contents: A Comprehensive Guide Symptom When visiting specific pages in a WHMCS installation, the page content appears to... Troubleshooting Facebook App Review Requests: A Comprehensive Guide Symptom You may receive an email from Facebook® with the subject New Developer Alert for... Troubleshooting Failed Email Sending with SendEmail API: Analyzing the Response Symptom When attempting to send an email using the SendEmail API command, you receive... Troubleshooting Free Domains: A Comprehensive Guide If you're expecting to order a free domain alongside a product, but upon reaching the... Troubleshooting Frequent Logout Issues: A Comprehensive Guide Symptoms Admins or users may report that the system frequently logged them out of... Troubleshooting Invalid License on HostGator Servers: A Step-by-Step Guide Symptom HostGator customers may experience an Invalid License message displayed when... Troubleshooting License Connection Errors: A Comprehensive Guide A connection error on the admin login page occurs when your server has been unable to... Troubleshooting Login Issues: A Comprehensive Guide Introduction If, when entering login details, the system redirects you to the login page... Troubleshooting MarketConnect Automated SSL Installation: A Comprehensive Guide With WHMCS MarketConnect, SSL certificates can be configured, approved and installed... Troubleshooting Missing v8.5 Update: Solutions and Guidance Symptom After navigating to Utilities > Update WHMCS  and clicking Check for Updates,... Troubleshooting ModelNotFoundException for [WHMCS\CustomField] Symptom After updating to 8.4, 8.5. or 8.6, you may experience an ModelNotFoundException... Troubleshooting Module Command Errors: A Comprehensive Guide Module Command Error Module Command Errors are errors returned from the module and not... Troubleshooting Order Form Issues: A Comprehensive Guide If you are experiencing a problem with the WHMCS order form, read on Order form not... Troubleshooting PayPal IPN Failure Emails: A Comprehensive Guide Symptom Whilst operating WHMCS version 8.0 or 8.1 and using the PayPal module, an... Troubleshooting Payment Issues: A Comprehensive Guide Should you have received a payment but do not see it recorded in WHMCS, check the... Troubleshooting Plesk Meta and Usage Data Enumeration: Solutions and Guidance Symptom After applying the 8.2.1 update, the metadata (CPU usage, CPU Load, and number of... Troubleshooting Plesk Panel Login Issues: Step-by-Step Solutions Symptom After applying the 8.2.0 update, certain environments may experience impeded... Troubleshooting Problems Accepting EULA After Update: A Step-by-Step Guide Symptom After applying the WHMCS 7.6 update, upon first logging to the administration... Troubleshooting Problems Adding Products to Cart: A Step-by-Step Guide Symptom Clicking Order Now on the shopping cart product selection page (cart.php) or... Troubleshooting Product Provisioning Problems: A Step-by-Step Guide Symptom WHMCS can automatically provision services either before or after payment or... Troubleshooting Question Marks in PDF Invoices and Quotes: A Step-by-Step Guide This article explains how to resolve the problem where PDF versions of invoices or quotes... Troubleshooting Service Invoice Generation: A Comprehensive Guide You may encounter a problem in which the system does not generate an  invoice for a service... Troubleshooting Status Monitoring: A Comprehensive Guide Server Status Monitoring may not display the uptime or CPU load statistics for a monitored... Troubleshooting TCPDF ERROR: [Image] Unable to Get the Size of the Image Symptom When downloading a PDF copy of a client's invoice after customizing the... Troubleshooting Twitter Sign-In Integrations: A Step-by-Step Guide Symptom You may see the following error when attempting to activate Twitter sign-in... Troubleshooting TypeError When Provisioning Plesk Services: Step-by-Step Solutions Symptom After applying the 8.2.0 update, you may observe a TypeError error message when... Troubleshooting Unexpected Service Terminations: A Step-by-Step Guide Symptom The system is unexpectedly terminating services (for example, hosting accounts).... Troubleshooting Unsupported Protocol Errors: Resolving TLS Support Issues Introduction A cURL Error code 35 Unknown SSL protocol or Unsupported SSL protocol... Troubleshooting Users Getting Logged Out When Downloading Invoices: Solutions and Fixes Symptom When a user attempts to download an copy of the PDF invoice via the client area,... Troubleshooting WHMCS v8.4 Not Appearing After Checking for Updates Symptom After navigating to Utilities > Update WHMCS  and clicking Check for... Troubleshooting Warning Messages: A Step-by-Step Guide PHP Warning messages should not be displayed under normal usage. Seeing them indicates that a... Troubleshooting Warnings on the System Health Status Page: A Comprehensive Guide This page explains how to resolve some of the common warnings in Configuration >... Troubleshooting Welcome Email Sending Issues: A Step-by-Step Guide Symptom You may experience an issue with unsent welcome emails. Cause... Troubleshooting Zero-Price Product Cart Issues: A Step-by-Step Guide Symptom After applying the 8.2.0 update, you may observe that some products cannot be... Troubleshooting a 'Down for Maintenance' Error During WHMCS Updates: Step-by-Step Guide Symptom While updating, you may see a Down for Maintenance (Err 2) error when you... Troubleshooting a 404 Error or Unexpected Page: A Step-by-Step Guide If products are enabled in MarketConnect, but the landing pages (eg. Website Builder, SSL... Troubleshooting a 404 Page Not Found Error: Step-by-Step Guide Symptoms When navigating to various sections of the Admin Area and Client Area, you... Troubleshooting a Blank Admin Dashboard After Updating: Step-by-Step Guide Symptom If none of the Admin Dashboard widgets are loading after you update WHMCS,... Troubleshooting a Blank Page or 'Oops' Error Message: Solutions and Tips Via The Admin Area To troubleshoot a blank page or Oops error message, navigate to... Troubleshooting a Blank Page or 'Oops' Error Message: Step-by-Step Guide Via The Admin Area To troubleshoot a blank page or Oops error message, navigate to... Troubleshooting a Blank iFrame During 3D Secure Payments via SagePay: Step-by-Step Guide Symptom After updating to WHMCS 8.4.0, installations using the SagePay payment gateway... Troubleshooting a Redirect Loop: Step-by-Step Guide Introduction A redirect loop occurs when a website tells your browser to redirect to a... Troubleshooting an 'Access Denied - Forbidden' Error: A Comprehensive Guide Access Denied - Forbidden An Access Denied - Forbidden error indicates that... Troubleshooting an 'Allowed Memory Size Exhausted' Error: A Comprehensive Guide If you see an error that resembles Allowed memory size of xxxxx bytes exhausted (tried to... Troubleshooting an InvalidArgumentException: 'Data Missing' in Carbon.php:425 Error Symptom After upgrading your server environment to PHP 7.4, you see the following error at... Troubleshooting and Debugging WHMCS API Calls: A Comprehensive Guide During the development process, you may need to verify whether your API code is working... Troubleshooting and Debugging WHMCS Hooks: A Comprehensive Guide Hooks are a way to customise and allow you to execute your own code when specific events... Troubleshooting and Resolving 'Down for Maintenance' Errors After performing an update, a Down for Maintenance (Err 2) or (Err3) error may occur when... Troubleshooting ionCube Errors: Comprehensive Guide To help protect the WHMCS software code, we obfuscate it using a system called ionCube®.... Troubleshooting ionCube Loader Error: File Type Mismatch Symptom After switching to PHP 8.1, you may see an ionCube Loader® error when accessing... Troubleshooting reCAPTCHA 'Invalid Domain for Site Key': Step-by-Step Guide Symptom Anywhere protected by a reCAPTCHA displays the error shown below, preventing... Troubleshooting v8.2 Update Absence: Solutions and Guidance Symptom After navigating to Utilities > Update WHMCS  and clicking Check for Updates,... Troubleshooting v8.6 Update Absence: Solutions for Missing Upgrades Symptom After navigating to Utilities > Update WHMCS  and clicking Check for Updates,... Understanding PayPal Checkout Subscription Log Entries: Insights and Analysis Symptom On WHMCS 8.7.2 or later, one of the following errors appears in the Activity Log... Understanding Service Next Due Date Changes: Causes and Solutions Introduction A service's Next Due Date may move to a date several months or years in the... Unlocking WP Toolkit Sales: Strategies and Implementation In WHMCS 8.2 and later, you can easily offer WP Toolkit. WP Toolkit makes working with... Updating Invoice Addresses: How to Make Address Changes WHMCS displays the address that you enter in Pay To Text on the invoices WHMCS generates.... Updating WHMCS Using the Automatic Updater: A Quick and Easy Guide The Automatic Update utility allows you to update WHMCS from directly within the Admin... Updating the System URL: Ensuring Accuracy in Your WHMCS Configuration To ensure that your WHMCS installation can function, your system URL setting must be... Upgrading PHP for WHMCS with cPanel MultiPHP: Step-by-Step Guide In order to comply with each version's requirements, you must sometimes upgrade the PHP... User Addition and Management: A Comprehensive Guide In WHMCS 8.0 and later, users can own client accounts. This allows one user to manage... Using WHMCS with PHP 8.1: A Comprehensive Guide You must meet certain prerequisites and prepare your system before you can start using PHP... Utilizing Maintenance Mode to Temporarily Block Customer Access: A WHMCS Tutorial Sometimes, you may not want clients to access the order form or Client Area. To prevent... WHMCS 8.7 Not Appearing After Checking for Updates: Troubleshooting Guide Symptom After navigating to Utilities > Update WHMCS  and clicking Check for... WordPress Hosting FAQs: Your Questions Answered In WHMCS 8.3 and later, you can easily offer automated WordPress® hosting for...