If your CD drive or DVD drive is missing or not recognized by Windows or other programs, so you cannot play or access a CD or DVD.

This problem is caused by two Windows registry entries that have become corrupted. To fix the problem, you have to use Registry Editor to delete the corrupted Registry entries. To use this method, you must be logged on to Windows as an administrator.

Windows Vista

1. Click Start, and then click All Programs.
2. Click Accessories, and then click Run.
3. Type regedit, and then click OK.
   HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlClass{4D36E965-E325-11CE-BFC1-08002BE10318}
4. In the right pane, 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 do not see the UpperFilters registry entry, you still might have to remove the LowerFilters registry entry. To do this, go to step 8.
5. On the Edit menu, click Delete.
6. When you are prompted to confirm the deletion, click Yes.
7. In the right pane, click LowerFilters.
   If you do not see the LowerFilters registry entry, unfortunately this content cannot help you any further.
8. On the Edit menu, click Delete.
9. When you are prompted to confirm the deletion, click Yes.
10. Restart the computer.
11. Click Start, click Computer, and then see whether the drive is listed. 

Windows XP

1. Click Start, and then click Run.
2. In the Open box, type regedit, and then click OK.
3. In the navigation pane, locate and then click the following registry subkey:
   HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlClass{4D36E965-E325-11CE-BFC1-08002BE10318}
4. In the right pane, 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 do not see the UpperFilters registry entry, you still might have to remove the LowerFilters registry entry. To do this, go to step 7.
5. On the Edit menu, click Delete.
6. When you are prompted to confirm the deletion, click Yes.
7. In the right pane, click LowerFilters.
   Note If you do not see the LowerFilters registry entry, unfortunately this content cannot help you any further.
8. On the Edit menu, click Delete.
9. When you are prompted to confirm the deletion, click Yes.
10. Restart the computer.
11. Click Start, click My Computer, and then see whether the drive is listed.
12. If the drive is not listed, remove and reinstall the existing drivers.