When I'm searching for something in the Developer Documentation of Xcode, I constantly get "File not Found"/"The requested file was not found in any documentation set."
The odd thing is, it still works. E.g., if I search for NSSound, I can find NSSound.
The error dialogue is invoked whenever it attempts to search as I type, which makes it particularly annoying.
This only happens when I select certain documentation sets (e.g., "iPhone OS 3.1 Library"). I tried deleting it & re-installing, but the same result. (Perhaps I didn't remove everything?)