This is an odd coincidence. I had a similar issue with an XP machine within the last week. On closer examination,an error code “39” was revealed. I could clearly see from the driver information in the properties dialog of the hardware manager that the system was failing to load the CD/DVD driver. Although I could see the drive in device management, the icon for the drive was no longer present in the “My Computer” explorer window. XP would redetect the drive, but failure to install the driver with an error code 39 was a constant.
If this is similar to the problem you are having, you may want to check the following links. The first is an old blog post that gives some credibility to a tool provided by Microsoft to address the issue (it convinced me to try the tool, rather than a manual registry edit), even if all of the circumstances don’t apply to your situation.
http://radified.com/blog/archives/000240.html
The second is a document from Microsoft outlining the underlying causes and the necessary steps to repair it. In this document you will find a download link for a tool (named “Guided Help”), that will allow you to make the required registry changes without having to manually search and edit. This tool also allows you to reverse the changes if the attempt is ineffective.
http://support.microsoft.com/default.aspx?scid=kb;en-us;Q314060
There is not quite enough detail in your post for me to tell if your situation is completely similar to the one I had, but this repair worked perfectly for me. Please read the information carefully, and if it applies, you can decide if you want to give it a go or not. I am not a certified tech, nor an expert by any means, so any changes you may decide to make are purely at your own risk when dealing with the registry. I offer this information only for your viewing pleasure. I hope this assists in pointing you the direction of a solution. Good Luck!
