I have a single Wordpress 4.9.16 website that is throwing Error 500s when taking many actions in the admin interface. When I try to do things like add a new category, nothing happens in the front end and my web inspector shows the error.
I have tried:
- Renaming my .htaccess file and letting WP rebuild a new one
- Increasing Wordpress memory limit
- Increasing PHP memory limit
- Disabling all plugins
- Re-uploading core files in wp-admin and wp-includes
And after taking each of those steps, I still experience an admin-ajax error 500 when trying to add a category.
My next steps are to either
- Change my theme
- Update to 5.6 current release.
I have a few questions, but basically it all comes down to how to fix my admin-ajax 500 error.
- If I change my theme to something out of the box (one of the Twenty ______ themes), and then change my theme back to my current theme (a child of Spacious Free), am I likely to experience big problems? Or will most/all of the configurations remain?
- Is it likely that I will be able to update to 5.6 if I'm receiving this error? It feels like this is a logical step in diagnosing the issue. I've been holding off because I haven't had a chance to test the site in 5.x, though.
- What else should I be looking for?