Yes, I know this is WPMU and I know I haven't yet upgraded to WP 3.0. It's in the works. But for now, I have a puzzling situation.
Unfiltered MU, the plugin, keeps dying on me. I installed it over a year ago, then in April it just quit working. The file for the plugin just suddenly wasn't there anymore. I re-added it and it started working again. Problem solved.
Now, it disappeared once again. Nobody except for me is working on the server, so I know it wasn't a human.
This time, however, when I re-add it to the blog's plugins directory and activate it, the entire admin console goes blank for every page of it. The site still runs, but the dashboard and all its pages is just a blank page. I can only restore things by deleting unfiltered-mu.php from the plugins directory. I know I need to first Deactivate, then delete and replace the file, but how can I Deactivate it when the admin screens disappear whenever it's in the plugins directory?