Troubleshooting the System Cron
If you encounter errors or issues involving the system cron or its daily automation tasks, see the sections below to start troubleshooting and resolve the issue.
You can troubleshoot cron-related issues using the steps in Check the Cron Job Status and Cron Failures.
- For general steps to troubleshoot problems in WHMCS, see Start Troubleshooting.
- For more information, see System Cron.
Cron Errors
You may encounter the following common issues:
| Error or Issue | Cause | Next Steps |
| The system is attempting to invoke the system cron correctly, but the cron job is not completing the run. | Cron tasks can fail for many reasons. | Cron Failures |
| You see a warning message stating that the system cron has not run within the past two hours. | Your system is not correctly invoking the system cron. | Cron Frequency Warnings |
Could not open input file: /path/to/crons/cron.php | The cron.php file is not present in the specified directory path. | Cron Input File Errors |
| The daily cron run is failing due to timeouts during Tenant Usage Metrics polling. | WHMCS cannot connect to a hosting server. | Cron Metrics Polling Timeout |
| During the daily automation cron run, the script takes a long time to complete, especially during the Executing System Queue step. | Processing times have increased due to the size of your WHMCS database. | Cron System Queue Timeout |
Your WHMCS is configured to perform the Daily System Cron during the hour of 9 am. However, the Daily System Cron did not execute within that hour as expected. | Your system cron is misconfigured. | Cron Time of Day Issues |
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 |
| The cron successfully finishes all of its tasks when you run it manually, but some cron job runs still do not succeed. | This type of issue may have many causes. | Intermittent Cron Failures |
No input file specified | The path to the cron.php file in your server’s cron job configuration is invalid. | No Input File Specified Errors |
| 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 |
Unable to communicate with the WHMCS installation | The cron.php, pop.php, or pipe.php files cannot communicate with the WHMCS installation. | Unable to Communicate Errors |
Error: Call to undefined function curl_init() | The system is terminating the cron job because the cURL extension is missing. | Undefined curl_init() 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: January 15, 2025