Decoder for windows media player? windows 7

[kaylafay]

all i want to do is play movies i have downloaded on my windows7 computer with windows media player and when i click to play certain movies it says"Windows Media Player cannot play the file. The Player might not support the file type or might not support the codec that was used to compress the file." do i need to download a decoder.will that make it work for me?????

 

[PhilFrisbie]

First., this is a Windows XP group.
Second, when downloading pirated movies you are on your own. . .