HERE IS THE FIX, I have new Compaq Presario laptop using Vista with this Optiarc DVD drive saying "Windows cannot load the device driver for this hardware. The driver may be corrupted or missing. (Code 39)"
I just tried this Jerry's recommendation, I couldn't get the Patchfix to download and work BUT... I did, with the help of COMPAQ tech support (my computer is still under waranty), figure out how to do Jerry's Idea manually and IT WORKED!
TO DO THIS: type "REGEDIT" in start search box to open the Registry Editor. In the directory tree click-expand the HKEY_LOCAL_MACHINE, SYSTEM,CurrentControlSet,Control,Class,{4D36E965-E325-11CE-BFC1-08002BE10318}, 0000. then in the right pane look for files with Upper or Lower Filters and then right click to delete them.