Make sure to check for any problems both during and immediately after the upgrade process.
While developing your own custom code, you may need to test and troubleshoot your implementation of the WHMCS hook system.
Troubleshooting system themes requires specific steps.
During the development process, you may need to verify whether your API code is working correctly.
Troubleshoot and resolve Unable to Connect errors while using the ImportAssist addon module.
Troubleshoot and resolve Plesk_Manager_V163::_getSsoRedirectUrl(): Argument #2 ($username) must be of type string errors.
Troubleshoot and resolve (S)FTP Backup - Uploading Failed errors.
Troubleshoot and resolve (S)FTP: Unable to open for writing errors.
Troubleshoot and resolve (S)FTP: Unable to write to temp file errors.
Troubleshoot and resolve Chrome™ browsers crashing when your customer makes a payment using 2Checkout.
Troubleshoot and resolve 404 Not Found: The requested URL was not found on this server. errors.
Troubleshoot and resolve 406 Not Acceptable errors.
Troubleshoot and resolve 500 Internal Server Error messages in WHMCS.
Troubleshoot and resolve Access Denied/Permission Denied errors.
Troubleshoot and resolve problems with failed account creation while provisioning a new hosting account.
Troubleshoot and resolve Action Failed Unable to auto-login errors.
Troubleshoot and resolve Oops! errors that occur while working with addon modules.
Troubleshoot and resolve You are attempting to access the admin area via a directory that is not configured. errors.
Troubleshoot and resolve Allowed memory size of xxxxx bytes exhausted errors.
Troubleshoot and resolve Application configuration file is not writable errors.