How to Delete Old WordPress Core Files

When WordPress is upgraded, some files are no longer used and are consequently set for removal.  On some occasions, like when WordPress is upgraded via the WordPress Dashboard, PHP has no permissions to delete the old core files; thus they remain on the server, making your WordPress site vulnerable to security threats.

The Old Core Files plugin can help with finding and deleting obsolete core files. The plugin lists old WordPress core files which are no longer required and takes the guesswork out of the process.

We recommend making a backup of your WordPress from within the WordPress Dashboard before adding or activating a new plugin. For instructions on how to backup WordPress, please refer to the following article from WordPress: WordPress Backups.

Install Old Core Files Plugin

To install the Old Core Files plugin on your WordPress site:

  1. Login to WordPress Dashboard by via http://example.com/wp-admin.php or http://example.com/wp-login.php (replace example.com with your actual domain name).
  2. From the left navigation menu, click Plugins > Add New.
  3. Search "Old Core Files" and click Search Plugins.
  4. Click Install Now > Ok.
  5. Click Activate Plugin.

View Old Core Files

To check your WordPress installation for old core files:

  1. Go to Plugins > Installed Plugins.
  2. Navigate to the Old Core Files plugin and click Settings.

Two lists of files will appear: existing and all. Old core files will appear under the list titled "Existing;" alternately, if there are no old core files, nothing will be listed.

Old core files will need to be deleted manually via FTP. If you need help with FTP, please see our video tutorials.

We also recommend deleting unused themes and plugins as they can be exploited by hackers and cause potential security issues. For more information on WordPress plugins, please read: