Try
DRM removal software that works with Windows Media Player.
I haven't seen any success in using lossless DRM removal software like
FairUse4WM or
freeme2 recently, but you can always use lossy DRM removal software like
Soundtaxi,
Tunebite,
Daniusoft Digital Media Converter or just re-record audio from your sound card using
direct sound recording software (the latter one works in real time only and can't preserve ID3 tags).