Media Errors....Digital Product ID?

Hello,
I am big into video and media design, and everything was
going to fine, till one day I tired to import mp3's to
the Mircrosoft Movie Maker timeline, and I got an error.
I restarted, and tried again, but still got the error.
The error deals with my Digital Product ID (whatever that
is). This doesnt just happen with Windows Movie maker.
It happens with anything that uses media (.avi's, mp3's)
except for .wav files, they seem to work ok. Does anyone
know what I should do? Thanks

Evan Herr
HuntHerr@cox.net