This error can pop up due to several causes. We need to check the logs for detailed information about the possible issues. Some locations are:
- Access logs:
- Error logs:
- .htaccess logs:
For example: PHP Fatal error: Allowed memory size of 41943040 bytes exhausted (tried to allocate 32768 bytes) in /home/some_path.php on line 330
Change PHP memory limit from 32M to 128M
Another case: PHP Fatal error: Call to undefined function is_favicon() in // PHP Fatal error: Cannot redeclare wp_get_user_request_data()
Check PHP version as it might be incompatible code after a plugin or WP upgrade. After that upgrade, you might receive some errors like this:
PHP Deprecated: Function create_function() is deprecated in /home/user/public_html/wp-content/plugins/random_plugin.php on line 250
This means that you will need to disable the problematic plugin and see if there is an upgrade available. I would also recommend to upgrade WP.
wp plugin deactivate plugin_name
If WP-CLI is not installed, check this link.
That’s all folks, see you later!