Something really weird started happening today, and i really have no idea what to do..
Well, i sometimes film my friends skating, and i have some of these clips on my computer, they are avi files. Now, everytime i try to play them on wmp, an error message comes up, as shown below. So again, they used to play fine, but now they dont at all.

So then I thought it was just a problem with avi files on my computer, so i tried playing an avi file that wasnt one of the skating clips. And it worked perfectly fine. So I have no clue what the problem is, could anyone help me please?
Thanks.