PHP error logs contains a record of errors that occurred during the server's operation.

• Default file name: error_log .
• Location of PHP error log depend on your server configurations. Please contact your host to find out where your logs are located at.

Here is an example of error log located in /public_html/ directory:

Here is an example of an error stored within error log:

 [12-Jun-2016 01:48:05 America/New_York] PHP Fatal error:  Class 'ZipArchive' not found in /public_html/ow_system_plugins/admin/controllers/plugins.php on line 504 

Check Errors Directory for more information on particular error and applicable solutions.