I have exactly the same problem and it looks like more people are having this bug.
BSplayer worked fine until I installed and removed some DVD-ripping tools and other software(TMPGenc).
Looks like we are not the only people with this problem:
http://forum.bsplayer.org/viewtopic....file+corrupted
Also removing and installing BSplayer again didnt change it. Couldn't watch any movies anymore, only SVCD's...
Same goes for the codecs.
Allthough after removing ffdshow-20020617.exe and reinstalling I was able to watch files again with BSplayer but still the error pops up.
I used a lot of players but this is the only I use now since it's the only player that plays my subtitles without any problems.