How can I Fix a .DAT media file…

I have a .DAT Video file on my system that any time I play it, it shows me the summary of the time it will play i.e. 45 minutes (Window Media Player) but when it play for 4 minutes it stopes and start from beginnin.

I have use some software like media fixer to repair it but the file still persist on thesame problem and also I cann’t seek.

Please I will be glad to know why and how I can fix the problem.

thank you