Optical drives don't show files

Hi all, My dvd drive would not show files on the cd. The icon changed to show
a cdrom or dvd was present. I could not see the folders or files. I changed
the drive to a new one...no luck. I plugged in a USB dvd burner I own and
found it also will not show files or folders. It also would show the icon
change upon insertion of a disk. I am thinking it is a driver problem or a
corrupted file that deals with optical drives. I was going to try
reinstalling service pack 2 on my tablet pc but could NOT figure out how to
do that. the update wizard reads my system and won't let me do it. Thanks in
advance for your help......
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Merry Christmas!