We can't see if others decrypted the files. Let's hope you know to keep backup copies of what you can't lose.
As to the CODEC try another player like VLC PLAYER.
And until further notice, use NINITE to get apps. Be brutal. Too many sites are bundling adware or worse. Here's more:
Well, that's harsh. Grif will share good links for what to scan with so you can find out what pest it was at http://forums.cnet.com/7726-6122_102-5509131.html?tag=posts;msg5509131
I had a virus that resulted in most of the files being damaged or corrupted. All of them are on the drive C. When I try to open mp3, I get "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". When I open .jpg file, I get "can't open this picture. The file appears to be damaged or corrupted." When I try to open a .doc file, I basically get the same response. The file extensions were not changed. I don't even know where to start. Any advice will be helpful