500 Internal Server Errors
The 500 Internal Server Error is a very general HTTP status code that means something has gone wrong on the website's server. Most likely, due to this error, the WordPress backend cannot be accessed anymore.
Common causes of HTTP 500 Errors
- The server uses some low resources.
- A corrupted .htaccess file.
- A third-party plugin conflict.
- A theme script conflict
Fixing 500 Internal Server Error Problem
Check for instance the PHP Memory Limit. Reaching or exceeding the PHP memory limit will cause the 500 internal server error. Check this article to see how to increase the allowed memory.
The .htaccess file is located on your WordPress root. WordPress uses this file to manipulate how Apache serves files from its root directory and subdirectories thereof. Most notably, WP modifies this file to be able to handle pretty permalinks. Read this WordPress Codex article to see the default content of the .htaccess file.
Using an FTP client or a cpanel file manager, navigate to wp-content/plugins and rename the plugins folder. This will disable all the plugins and should restore the access to the WordPress login box. Rename back the folder to original name: plugins. Go to WP Admin > Plugins and activate one by one the plugins until you find the one causing the troubles.
DIsable for a moment your theme and activate a default WordPress theme. For more details, see this basic debugging process article.
The Error log file
Any 500 error should be logged in an error.log file from your server or cpanel. Check your WordPress root after an error.log file. This should contain details about the 500 error. You are welcome to contact us using the contact form on this page and paste the last lines from this file. This way we are able to help you more.