I was just informed of a fix for what I call the “haunted keyboard” bug in Whidbey (April CTP/Beta 2). It occurs after having pinned one of the windows (like the Server/Database Explorer). Sometimes the backspace and delete key (and perhaps others) stop working. The other keys on the keyboard seem to work but you can't remove anything... strange. Anyway, to fix it, (thanks to Bill McCarthy) you need to set focus on the pinned window's tab and press Alt-Enter and set focus back to the editor window. It also helps to stamp your foot (right foot) three times and shout “Begone thou evil spirit! Never darken my backspace key again!
July 2, 2005: I just found this same problem on the June CTP. It's apparently harder to find than they thought...

Thanks Bill, laughed so hard that I woke up my wife... now I'm in the poop.
That'll teachme to read your blog in bed at 3 in the morning....
Thanks for this. This thing happens to me all the time. I actually stopped playing around in VS 2005 because of this.
I didn't get really the solution. can you explain more please?
These issues have all been repaired in the current builds. In the September CTP the fix is to use fixed-pitch fonts. In the earlier CTPs if you ALT right-click on the menu, the keyboard should unlock.
I have this issu in the released verions on VS.NET 2005, and I can't shake the look on the keyboard, needs instant suggestions && solutions.