Pre-downloaded video clips (which were fine) not playing b..

For some reason when I'm trying to watch video clips that I've previously
downloaded I only get about 90 seconds of the video (some should be 15 mins
or longer), when it gets to the end the video freezes but the sound continues.

I've tried using lots of different media players so it appears to be a
problem with the video files, which up until recently have been playing
perfectly.

If anyone's got any bright ideas they'd be much appreciated as this is
driving me insane!!

Many thanks
Simon

For some reason when I'm trying to watch video clips that I've previously
downloaded I only get about 90 seconds of the video (some should be 15 mins
or longer), when it gets to the end the video freezes but the sound continues.

I've tried using lots of different media players so it appears to be a
problem with the video files, which up until recently have been playing
perfectly.

If anyone's got any bright ideas they'd be much appreciated as this is
driving me insane!!

Many thanks
Simon