windows media player

Hello
I used Windows media Player to play some MP4 videos and now I cannot remove the files. I have checked the original location and the video folder - also checked the Flipshare software. No duplicates exist.
I called Flip and they feel there may be corruption. Maybe Windows 7x64 cannot support mp4 files. I have all the windows upodates.
I have had alot of trouble with Flip; does anyone know how to clear up my Media player so I can get rid of those files. They are under "Other media" not videos.
If I use add/remove or Revo, how do I get the media player reinstalled?
Thank you foor your help