I have been using Windows 7 Professional 64 for about 2 weeks without incident and have been loving it. Unfortunately, just now it seems to have forgotten my CD/DVD drive drivers for my Lite-On LH-20A1L. I'm getting a code 39, "Windows cannot load the device driver for this hardware. The driver may be corrupted or missing," yet when I try to fix the driver, I just receive the message, "Windows has determined the driver software for your device is out of date." I have disabled and re-enabled the device several times, with and without reboots, as well as uninstalling the drivers, with and without reboot. I have also checked for loose wires, etc. internally, and found that even changing out to different SATA wires helps nothing. In addition, an external Plextor 610U Drive which had also worked in the past has the same situation. I have not been doing anything out of the ordinary in terms of use, I just discovered it when I was trying to load a piece of software, and discovered the drive was no longer recognized, even after I installed some Adobe programs from the drive just yesterday. I am completely baffled by this, and any help with this matter would be greatly appreciated.

Here's one way you can get the drivers loaded again. Don't know what OEM machine you might have, but go into device manager and remove the hardware that's giving you problems. Then rescan your hardware and it'll detect it and reload the drivers.MCSE, MCSA, MCDST [If this post helps to resolve your issue, please click the "Mark as Answer" or "Helpful" button at the top of this message. By marking a post as Answered, or Helpful you help others find the answer faster.]

I tried that already. I'm sorry I wasn't clear enough on that in my above post. I try and receive the error, "Device driver software not successfully installed." As for the OEM, that would be, well, me I suppose. It's home-built. I don't think that's too helpful, though.

Ahh well thanks for adding more to the info, so others can come up with some idea's. Actually yes, knowing its home built means now we can delved into your motherboard info. What is the specific motherboard and model? Someone will keep narrowing down the issue.MCSE, MCSA, MCDST [If this post helps to resolve your issue, please click the "Mark as Answer" or "Helpful" button at the top of this message. By marking a post as Answered, or Helpful you help others find the answer faster.]

What about trying a System Restore to before this happened?Rich

This issue occurs if the multi disk installation has added filter drivers that are not compatible with the NEC drive in the DVD driver. I suggest that you follow the steps below to remove the filter drivers. Step1: Delete filter driver===================== 1. Click "Start", in the Start Search box type "regedit" and press Enter. 2. Navigate to the following key: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E965-E325-11CE-BFC1-08002BE10318} 3. Right click on "Class", click "Export"; please name the file as "RegBackup" (without quotation marks) and then save it to the C:\ drive as a backup. Note: In case we need to undo the modification, we can double click this RegBackup.reg file to restore the registry key. 4. Highlight this key, on the right pane, check if the "Upperfilters" and "Lowerfilters" values are present. If so, please right click on the values and select "Delete" to remove them. After deleting filter drivers, please reload the drivers. Step2: Reinstall driver===================== 1. Click "Start", in the Start Search box type "devmgmt.msc" and press "Enter". 2. Expand "DVD/CDROM Drives". 3. Right click the listed DVD/CD-ROM, and click "Uninstall". Please uninstall all devices. 4. Restart the computer. The drivers will be loaded automatically. If the issue still occurs, please remove third party burning programs one by one and check if the CD/DVD works after removing.Arthur Xie - MSFT

To my delight, this resolved an identical problem in Vista SP2. Thank you!!