I installed 11.10 clean from the CD and I cannot switch users. When I am logged in and click either another user's name or "switch user account" from the users menu, I get a blank screen with just a flashing cursor top left. The only way to get back to something usable is to ctrl+alt+F7. The same thing happens when clicking switch user from the lock screen. Any ideas - I couldn't find a bug report that matched or figure out where best to post a new bug.
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