if you can help me then i will think your a god lol seriously please help me

[WelshWizard2004 0]

I know this is my first post but i cant find anyone to help me with this prob i have , i have downloaded some video files completely , but when i play them the duration for example says 15 seconds when i know its at least a couple of minutes. and if i move the seek bar it will show a small bit of that part of the file but its annoying me now as i have to do a project for college and its messing all my files up. anyone know how to play them with the full duration etc or anything i need to do thanks peeps