UPPER & LOWER FILTER

In order to delete upper and lower filters you're going to have to edit the registry.
The usual cautions apply. If the registry is not edited properly your whole system can crash.

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.

* UpperFilters
* LowerFilters
* UpperFilters.bak
* LowerFilters.bak

5) If any of the above keys shown in step 4 are listed, right-click on them and choose Delete
6) After deleting the keys, close the Registry Editor
7) Reboot your computer
8) 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


Clearing NVRAM
To clear NVRAM for all devices and restart the computer:

Enter the system setup program.

Press the right-arrow key to move to the Advanced menu.

Select the Boot Configuration submenu by pressing <Enter>.

Press the down-arrow key to highlight Reset Config Data. Then change the setting to Yes (see "Boot Configuration Submenu").


Press <F10> to exit the program and restart the computer.