Both DVD/CD drives not initialising and raising...

Question

This problem above happened around 6 months ago when taking photo software off the computer via add and remove programs and found afterwards that the two CD drives didnot fuction and had esclamation marks next to the drives in the device manager.I searched the web for a fix and this to was to run REGEDIT & find the file name(4D36E965-E325-11CE-BFC1-08002BE10318)and open this file and deleted the upper & lower filters.Then went back into device manager to search for a drivers on the C/drive which then loaded ok and both drives were back to normal.But for some odd reason these have become un-initialised again.I cannot repeat the abve fix as this file starting 4D36 doesnot exist anymore.Can you help.Thanks Phil