The game disk installed and runs fine, but the DLC disk now appears empty. When I right-click the dvd drive in "My Computer" and select "open", it doesn't list any files whatsoever. It's not struggling to read the disk, rather Windows actually thinks there's nothing on the disk so the drive won't even spin up.
I tried the whole safe-mode trick, but that does nothing. The DLC disk appears empty in safe mode too.
This is very strange, because I think I was able to read the DLC disk back when I bought this new. I doubt the DVD drive has gone bad, since it reads the game disk just fine.
I use Windows XP, SP3 if that helps. My drive is an NEC ND-3550A DVD-RW.
I'll try mapping my brother's DVD player as a virtual drive and install over LAN later tonight, but that won't satiate my curiosity. Why is this happening in the first place?