File Type Not Permitted when Uploading Media

If you are uploading files in the media library or within form elements on your WordPress site and receive this error:

Sorry, this file type is not permitted for security reasons.

The way to resolve this it to edit the wp-config.php file and copy/paste the below code snippet above the /* That’s all, stop editing! */ line:

define('ALLOW_UNFILTERED_UPLOADS', true);

Another option is the WP Extra File Types plugin, which allows you to control which file types can be uploaded.