QuickTime Player can't open "_Movie on 4-20-13 at 7.31 AM (8).mov" because the movie's file format isn't recognized.What does this mea?How do i open it?Thanks.
Try downloading VLC Player from here (free)
Sometimes Quicktime needs certain codecs to open certain movie formats. Instead of installing them, I find that VLC will open most of them, unless of course the movie is damaged.
Mov files are native to Quicktime, they should play, you may have a corrupted file, if there was an error message when you tried to play it, post it here.
This is a link to a sample .mov file, it is from Apple. Try downloading and playing it, if it works your file is either corrupted or is not actually a .mov file.