If you are using Windows XP, go to C:\WINDOWS\system32\drivers
Check if you have a file called cdfs. This driver is needed for playing files which are using the CDFS file system.
If you don't have, get it from the Windows CD.
For other versions of Windows, it should be slightly similar. Locate the path where drivers are stored.
Edit: typo error.
You can download the cdfs.sys driver
here if you don't have Windows CD. Otherwise, borrow from your friends.
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