Symptom
After upgrading your server environment to PHP 7.4, you see the following error at Help > System Health Status:
InvalidArgumentException: Data missing in /path/to/whmcs/cs/vendor/nesbot/carbon/src/Carbon/Carbon.php:425
Cause
Your system's PHP version is not compatible with your current WHMCS version.
For more information on WHMCS's PHP version requirements, see System Environment Guide.
Solution
Move to a compatible PHP version for your current WHMCS release. For example, for WHMCS 7.10 you could use PHP 7.3.
The End! should you have any inquiries, we encourage you to reach out to the Vercaa Support Center without hesitation.