Whenever I insert a CDR with data already on it into either drive on my Vista Ultimate computer it will not read the files on the disk. All it wants to do is write to it. How can I turn this off so I can read my backup files on this computer?

I can read the data just fine on my XP based laptop-- but Vista will not read any files on the disk. It sees the folder structure but does not see the files. This just started today after I burned a disk and will not go away.

I have tried restarting the machine and no change.