My cd-rom/dvd drive is missing

Where did my CD-ROM drive go?

Just an interesting problem I had the other day: I open up "My Computer" and saw that the CD-ROM drive icon is missing! No problem I though - Maybe it is not assigned a drive letter. So I went to computer management and saw it wasn't there either. OK...? So I boot up in the BIOS and there it was detected fine. Still no problem, I thought. I will just uninstall/reinstall the driver. That is when I got this error:

The device is not working properly because Windows cannot load the drivers required for this device (Code 31).
So I've discovered from Microsoft's KB articles that there is a registry fix for it. The following error messages points to the same problem:
A driver for this device was not required, and has been disabled (Code 32 or Code 31) and
Your registry might be corrupted. (Code 19) You might receive the following notification message: Windows successfully loaded the device driver for this hardware but cannot find the hardware device. (Code 41)
The cause could be of some dvd or cd-rom burning software that you have uninstalled. This is the fix: (Remember to backup your registry first)

Step 1: Start Registry Editor

Start Registry Editor.

Step 2: Delete the UpperFilters registry entry

1. In Registry Editor, expand My Computer, and then expand HKEY_LOCAL_MACHINE.
2. Expand SYSTEM, and then expand CurrentControlSet.
3. Expand Control, and then expand Class.
4. Under Class, click {4D36E965-E325-11CE-BFC1-08002BE10318}.
5. In the details pane of Registry Editor, on the right side, click UpperFilters.
   
   Note You may also see an UpperFilters.bak registry entry. You do not have to remove that entry. Click UpperFilters only.
   • If you see the UpperFilters registry entry in the details pane of Registry Editor, go to step 6.
   • If you do not see the UpperFilters registry entry, you still might have to remove the LowerFilters registry entry. To do this, go to "Step 3: Delete the LowerFilters registry entry."
6. On the Edit menu, click Delete.
7. Click Yes when you receive the following message:
   Are you sure you want to delete this value?

The UpperFilters registry entry is removed.

Step 3: Delete the LowerFilters registry entry

1. In the details pane of Registry Editor, on the right side, click LowerFilters.
   
   Note You might see a LowerFilters.bak registry entry. You do not have to remove that entry. Click LowerFilters only.
   
   If you do not see the LowerFilters registry entry, unfortunately this content is unable to help you any more. Go to the "Next Steps" section for information about how you can find more solutions or more help on the Microsoft Web site.
2. On the Edit menu, click Delete.
3. Click Yes when you receive the following message:
   Are you sure you want to delete this value?
   The LowerFilters registry entry is removed.
4. Exit Registry Editor.

Step 4: Restart your computer

Restart your computer. After you have done this, try to access the CD or DVD drive. If you can access the CD or DVD drive, and if you do not receive an error message, the problem is resolved. You can reinstall your CD or DVD writing or recording software.

If you cannot access the CD or DVD drive, or if you receive an error message, unfortunately this content is unable to help you any more. Go to the "Next Steps" section for information about how you can find more solutions to the problem.

I only had an "upper filters" entry. When I removed it and rebooted, all was well again.