Code 39 Error with DVD/CD-ROM drives in Windows XP or Vista

1. Close all open programs
2. Click on Start, Run, and type REGEDIT and press Enter
3. Click on the plus signs (+) next to the following folders HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E965-E325-11CE-BFC1-08002BE10318}
4. This folder is the DVD/CD-ROM Drive Class Description in the registry. Look for any of the following names in the right hand column.
5. UpperFilters
6. LowerFilters
7. UpperFilters.bak
8. LowerFilters.bak
9. If any of the above keys shown in step 4 are listed, right-click on them and choose Delete
10. After deleting the keys, close the Registry Editor
11. Reboot your computer
12. Open My Computer and check to see if your CD or DVD drives have returned. You may also want to open Device Manager and verify that the yellow exclamation and error code on the CD or DVD drive is gone.