Blank php screens in wp-admin

Hi everyone,

I have been away from my site for about a week and it seems it has all gone down hill since then. Any help would be greatly appreciated.

Issue: The site works fine when not logged in, but once logged in the header does not show. This led to me trying to fix that issue, I went into the admin page and wanted to see if a plugin was the issue… I couldn’t access the plugin page, for that matter, I can’t access any .php page in the wordpress admin, they load a little and then are blank!

I already disabled all the plugins to see if that was the issue, by renaming the plugin folder in my FTP, but that didn’t help!

My theme has an update, but that made it worse, so I reinstalled the old version.

This happens in chrome, safari, and firefox.

Thoughts and suggestions would be great!