A 500 error is a generic server error. Please contact your webhost to review your server’s error log. It should contain a more detailed error.
If there are no further details in the error log, the error may be caused by a plugin or theme conflict. The fastest way to rule out conflicts is to deactivate all non-Yoast plugins and switch to a standard theme like Twenty Seventeen. If this resolves the issue, you have a conflict and should activate one plugin at a time until you locate the conflict. Finally, after all plugins are active, switch to your theme. This will narrow down the conflict to a specific plugin or theme.
If you are unfamiliar with checking for conflicts, we wrote a small guide that will walk you through the steps. You can find it here: How To Check For Plugin Conflicts
