My first post on this forum, dorry if this has been covered before...

1. I Download some music in WMA 128KB/s format. This is Windows DRM
protected music.
2. If I drag & drop the music onto the portable device the portable
device won't play it as it has no licence. So I must use Media Player
to transfer the music & licence to the portable device.
3. Use WMP(v10) to transfer the music from my hard disk to the portable
device.
4. Music plays, I'm happy.
5. I take a copy of the music files from the portable device PLUS the
licence file and back them up on my PC. This seems sensible, just in
case I loose/damage them etc.
6. Days later, I'm running low on space on my portable device, so I
delete the above music to free up space.
7. Several weeks later I want to listen to that music again, so I free
up space on my portable device and locate my backed-up music files &
licence and using explorer, drag & drop them on the device (because its
quicker than going using WMP to transfer the files).
8. Device won't play the music, it says the files are protected - why
won't the portable device play the music?