This hasn't happen in a long, long time, but I got a 500 error on the tongfamily.com site, which is pretty bad. The troubleshooting is pretty complicated, but it comes down to, on Bluehost.com:
- Make sure you have ssh access to the site. You should enable ssh access on the Bluehost.com Cpanel then upload you public ssh key and make sure that your ~/.ssh/config points to it.
- Now you can ssh into the client and then follow the directions on WP Beginner where are first to move .htaccess to .htaccess.bak. many errors are related to this. This actually didn't help.
- Then move wp-content/plugins to wp-content/plugins.old to delete all the plugins
This actually got my site back to life, you you know that it is a plugin problem.
Now you have to to through the process of reinstalling them 1 by 1:
- Jetpack. This is the key plugin that allows connection to WordPress.com. This was super broken now that the plugin is gone. So Remove the site on WordPress.com.
- I actually then had an .htacess problem and a 404 error because I was using word fence, so the permissions are too tight on the site.
- Then reinstall jetpack again and it seems to basically work.
- Now you try again to make it work, but JetPack seems still to have these errors, so try to install word fence to fix it.
- The one error I get with Wordfence and with the whole site is that it requires a later version of PHP. WordPress says it needs 7.3, but Bluehost only supports 7.2 and looking at wordfence, it says it needs 5.3 which is confusing to say the least.
- For some reason, turning on pretty permalink seems to solve the JetPack problem.