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PayPal IPN Failures

Troubleshoot and resolve problems due to PayPal® Instant Payment Notification (IPN) failures.


PayPal Old Transaction Errors

Troubleshoot and resolve Referenced transaction or order is too old errors while using a PayPal payment gateway module.

PayPal Payments Issues

After attempting to migrate to the new PayPal Payments payment gateway module from a previous PayPal® module, you are experiencing problems with subscriptions.

PayPal Security Errors

Troubleshoot and resolve L_SHORTMESSAGE0 => Security error errors while using a PayPal payment gateway module.





PayPal® Not Working Errors

Troubleshoot and resolve Things don't appear to be working at the moment errors while using a PayPal payment gateway module.


PE101 Errors

Troubleshoot and resolve Error Code PE101, Account is not approved to sell., or Account has been closed. errors while using the 2CheckOut payment gateway module.


PHP Execution Time Errors

Troubleshoot and resolve PHP Fatal error: Maximum execution time of 300 seconds exceeded in /path/to/file.php errors in WHMCS.

Plesk Connection Errors

Troubleshoot and resolve 503 Service Temporarily Unavailable, Page not Found, Timeout, or 502 Bad Gateway errors.


POP3 Cron Not Running

Troubleshoot and resolve a POP3 cron not running emails and WHMCS Pop Cron Did Not Run errors.

POP3 General Error 3988 Errors

Troubleshoot and resolve General error: 3988 Conversion from collation utf8mb3_unicode_ci into latin1_swedish_ci impossible for parameter errors.