PLS Help :: dark video files, no matter what codec, player or updates

I re-installed Win XP, and copied my mpg’s avi’s etc.
When I played the files in Media player they were all dark, you can hardly see anything, adjusting the brightness doesn’t work either. I got codecs, updates other players. but Vids don’t work on my PC??? Can anyone PLEASE help me!!!

This is a shot in the dark, but did you install the latest video drivers after reformat?