PHP Info
WHMCS displays a variety of information about your server and the current PHP configuration.
You can view this information at Utilities > System > PHP Info.
PHP Info
The information that the system displays includes PHP options and extensions, the PHP version, server information, and php.ini configuration settings currently in use for the WHMCS Admin Area.
You can use this information to verify compatibility with supported modules and to quickly verify server information while troubleshooting system-related issues.
These details come directly from the
phpinfo() PHP function and WHMCS does not edit or change them.Troubleshooting
For steps to troubleshoot PHP-related errors, see Troubleshooting PHP.
You may encounter the following common issues:
| Error or Issue | Cause | Next Steps |
500 Internal Server Error | There was a problem while processing a request. | 500 Internal Server Errors |
Allowed memory size of xxxxx bytes exhausted (tried to allocate xxxx bytes) | WHMCS has reached maximum amount of memory available to PHP on your server. | Allowed Memory Exhausted Errors |
Down for Maintenance (Err2) | There is a mismatch between the database version and WHMCS version or PHP version. | Down for Maintenance Errors |
PHP Fatal error: Class 'xxxx' not found in /path/to/whmcs/vendor/whmcs/whmcs-foundation/lib/Exception/Handler/ExceptionLoggingTrait.php on line 0 | A core WHMCS file is missing. | ExceptionLoggingTrait Errors |
A fatal error occurred while fetching the update | This error may occur due to issues with PHP, your server, or your network. | Fatal Error Fetching Update |
Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 20480 bytes) | The system is terminating the cron job because it has exceeded the memory_limit value of 32 MB. | Fatal Memory Size Errors |
| Admins or users report that the system frequently logged them out. | You have misconfigured PHP, a proxy, or CDN on the server that hosts WHMCS, there is insufficient disk space, or there is a problem with the visitor’s IP address. | Frequent Logouts |
InvalidArgumentException: Data missing in /path/to/whmcs/cs/vendor/nesbot/carbon/src/Carbon/Carbon.php:425 | Your system’s PHP version is not compatible with your current WHMCS version. | InvalidArgumentException Carbon Errors |
Site error: the ionCube PHP Loader needs to be installed. This is a widely used PHP extension for running ionCube protected PHP code, website security and malware blocking. Please visit get-loader.ioncube.com for install assistance. or Site error: the file /path/cron.php requires the ionCube PHP Loader loader to be installed. | There is a configuration problem with ionCube Loader®. | ionCube Loader Site Errors |
Legacy Smarty Tags: The system detected that legacy Smarty tags may be in use and that the Allow Smarty PHP Tags setting is enabled. | A theme or email template contains deprecated code or you have enabled Allow Smarty PHP Tags. | Legacy Smarty Tag Errors |
A license key is required. If you don't have one, please visit www.whmcs.com to purchase one. | There is an issue with the PHP sessions configuration in your server environment. | License Key Required Errors |
| When a user downloads a PDF invoice in the Client Area, the system logs them out. | pdo_mysql clients in your server configuration caused unexpected behavior in PHP. | Logout During Invoice Download |
Unable to find the socket transport "ssl" | There is a problem with PHP on your server. | Nominet Socket Transport Errors |
| You are experiencing problems that relate to stale cached data or PHP script execution. | The OPcache PHP extension is enabled. | OPcache Warnings |
PHP Fatal error: Maximum execution time of 300 seconds exceeded in /path/to/file.php | The max_execution_time limit is too low for a specific task or operation. | PHP Execution Time Errors |
Required function is not available or Required function base64_decode is not available | This error indicates that a necessary function is not installed on the server or is disabled in the configuration. | Required Function Errors |
Segmentation fault | This error does not directly relate to the WHMCS software and can occur for many different reasons. | Segmentation Fault Errors |
| The system is not removing sessions from the location in your session configuration. | There is a problem in your PHP configuration. | Sessions Are Not Removed |
| The uptime or CPU load statistics for a server are not displaying properly. | The server does not use a Linux®-based operating system, the status directory is inaccessible, or required PHP functions are disabled. | Status Monitoring Display Issues |
An Error Occurred. Please try again. | The server environment is missing the expected nd_pdo_mysql PHP extension. | Stripe Try Again Errors |
| The installation process became stuck on Step 4. | Your system or its configuration do not meet our system requirements. | Stuck Installation Process |
| You experience timezone-related issues in WHMCS or while running WHMCS automation. | There is a timezone misconfiguration or a mismatch between the webserver’s PHP configuration and the cron engine’s PHP configuration. | System Timezone Issues |
Call to undefined function PHPMailer/
HPMailer/scapeshellarg() in /path/to/whmcs/vendor/phpmailer/phpmailer/src/PHPMailer.php:1730 | The escapeshellarg function is disabled in your server’s PHP configuration. | Undefined PHPMailer Function Errors |
Whoops\Exception\ErrorException Maximum execution time of 30 seconds exceeded | The system is terminating the cron job because it has exceeded the max_execution_limit value of 30 seconds. | Whoops Exception Errors |
Last modified: 2025 May 8