Why some files play and some don't?

[Bauerlein99]

I am new to VLC. Alot to learn. I have an extensive ITunes library and I am starting to understand a little about codecs, file formats so I know ITunes is AAC -Mp4. My question is why do some songs/files play and others do not? Here is the message I get when I tryu to play some of my songs:
mp4 error: drms_init(priv) failed (invalid argument)

For what it's worth, I did try to find the answer pretty hard before I posted this topic/question. If anyone can kind of point me in the right direction I would sure appreciate it. Hopefully someday I will have the requisite knowledge of VLC to provide guidance to thers that come after me. Thanks in advance.

[Lotesdelere]

mp4 error: drms_init(priv) failed (invalid argument)

These files are encrypted with DRM and VLC can't play such files.

[Bauerlein99]

Thanks for the knowledge. I'm guessing that Apple usses DRM on many of the songs I got from them. So am I stuck with using ITUnes for my music?
?

[Lotesdelere]

Or find a way to remove the encryption

[midas02]

Requiem is a java software that will strip the DRM off your iTunes library. Do a Google search on 'java requiem' and you should have no problem finding it.