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An internal server error, also called a 500 error, is one of the most frustrating issues a WordPress user can encounter. It appears for no particular reason, leaving you with a page lock and no specific information about the problem. Don't worry though, there are many ways to solve this problem. Let's look at some of them now.
1. Check the .htaccess file
The first step in troubleshooting an internal server error is to check the .htaccess file. This configuration file is used to manage many aspects of the server, but it is also prone to errors that can cause a problem.
To check this, you need to log in to your server via FTP or your hosting admin panel, and then locate the .htaccess file in your WordPress root directory. Then rename the file, e.g. to “.htaccess_old”, which will deactivate it. If your problem goes away, you know the .htaccess file was the culprit. You can then create a new .htaccess file by entering the default WordPress rules.
2. Increase PHP memory limit
Another common cause of an internal server error is PHP memory running out. This can happen when a process on your site starts using more memory than is available.
To increase the PHP memory limit, you need to add this line of code to your wp-config.php file: define('WP_MEMORY_LIMIT', '256M');. This code will increase the memory limit to 256 MB, which should be enough for most sites.
3. Disable all plugins
Sometimes the problem may lie with a specific add-on or a conflict between add-ons. To check this, it is best to disable all plugins and then enable them one at a time, checking after each one to see if the problem returns.
If you can't get to the WordPress admin panel, you can do so via FTP or your hosting admin panel. Just rename the plugins folder ("plugins" by default) to something else to disable them all. You can then go back and rename the folders for individual plugins to find the culprit.
4. Update your PHP version
An outdated version of PHP can also cause problems such as an internal server error. We recommend using the latest stable version of PHP.
To do this, you need to go to the hosting administration panel and find the option to update PHP. The process may vary depending on the hosting, but it is usually quite simple. Just remember to make a full backup of the site before updating.
5. Contact your hosting provider
If none of the above solutions helped, the problem is somewhere else, perhaps at the server level. In this case, it is best to contact your hosting provider and ask for help.
Knowing these methods should help you quickly resolve an internal server error issue in WordPress. Remember that the most important thing is the elimination method - try different solutions until you find the one that works. Good luck!