Given the limited info we have to work with, I would say that BF2 has detected some sort of blacklisted software on your computer. This may include a virtual drive such as Daemon Tools or Alcohol. I run the game off of an image mounted with Daemon Tools but others have reported problems. Your best bet is to disable all virtual drives (if any are present). An easy way to check is to go to My Computer and look to see if you the number of optical drives there is the same as the number of physical optical drives in you computer. If that doesn't work, try uninstalling Nero if you have it... this program gives me all sorts of problems that are seemingly unrelated. Good luck.