beginner need help with wmv file problem

I run windows xp professional version 5.1

I have not had problems running wmv. clips until recently.

utube clips will run fine, but wmv. files emailed to me run but the screen goes black every second and flashes a moment of the clip running then goes black again.

Any ideas ??

try this.....
go to tools options then performance tab on video acceleration then set all the settings on except the full screen mode

What player do you use?
Did you try different player?