Unexplained symbol WINDOWS 7

[Segilla]

I've been housekeeping, shuffling files about and deleting etc and have ended up with a half black rectangle to the left of some main Folders which do not now work as previously. When I move the cursor out of the Folders column the black images disappear and vice versa.
How do I get rid of the symbol and get back to normal?

[VHG]

>>>>How do I get rid of the symbol and get back to normal?

"Shuffling files about and deleting" sound very dodgy to me and you may have deleted or moved something you should not have.

Go into System Restore and go back to an earlier version of Windows and hope the problem sorts itself out.

[bassmanjack]

You could try 'System Restore'

http://www.youtube.com/watch?v=oGXbMyFaROw