WMV problems

Hi ppl.
I tryed to use bsplayer to play some WMV files and i get a message say "Unknown format"
I have Windows XP (with lot of codecs installed also) and i can play the files with Media Player..
What can i do ?
Thank you

[adicoto]

Install win media player codecs
http://www.microsoft.com/windows/win...ad/default.asp

[pietro]

But if you can play it with Media Player wouldn't that mean you already have the right codec?

I have some wmv files that won't play with anything but Media Player as they have a license, some stupid DMR thing I think it's called.