Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

A driver (service) for this device has been disabled. An alternate driver may be providing this functionality. (Code 32)

No drive letter show in device manager, and the DVD/CD drive is unusable because it couldn't be seen. This all happened, when I starting using a new, external USB hard drive from Buffalo. I have Win-7 64bit. Everything else looks to be working fine.

I even tried to hook up, and external DVD that had worked fine in the past. Just too slow and ate up memory, so I never used it. It tries to use the same drives, and when you click to update drivers, it says this is the best one.

Even if I want to use the factory win 7 re-installation DVD, How could I? I've got no drive to install it from in this situation. I am lost here, and Buffalo tech was of no help at all. Just said that he could not help.

Any help would be much appreciated.

share|improve this question
I have this same problem with my USB drivers on Windows 8. They were working fine then I rebooted for some updates and now I can't get them to work. – Devil's Advocate Jul 7 '13 at 11:37

In this case, the Device Manager Code 32 error is probably correct. There may be a driver or service that is missing which is preventing Windows from accessing your DVD/CD drive. These drivers are often referenced as Upper or Lower Filters. I find this to be a common problem after installing or uninstalling software related to CD/DVD drives (e.g. DVD burning software). What often has happened is that a driver is referenced in the Windows Registry but the file doesn't exist.

Here's how to check for Upper or Lower filters that are interfering with the proper function of your CD/DVD drive (adapted from these instructions on

  1. Click on the Start button.
    • If you're using Windows XP, also click on Run.
  2. In the Search programs and files box (Windows 7 and Windows Vista) or the Run textbox (Windows XP) type regedit and click OK or press the ENTER key.
    • This will open the Registry Editor program.
    • Important: Changes to the registry are made in these steps. Take care in making only the changes outlined below. While it's not a necessary step to complete this process, I recommend that you play it safe by backing up the registry keys you're modifying.
  3. Locate the HKEY_LOCAL_MACHINE folder under Computer/My Computer and click the |> or (+) icon next to the folder name to expand the folder.
  4. Continue to expand folders until you reach the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class registry key.
  5. Click on the |> or (+) icon next to the Class key to expand it. You should see a long list of subkeys open up under Class that look something like this: {4D36E965-E325-11CE-BFC1-08002BE10318}.
  6. Click the registry subkey {4D36E965-E325-11CE-BFC1-08002BE10318}
  7. In the results that appear on the window on the right, locate the UpperFilters and LowerFilters values.
    • Note: If you only see one or the other value, that's fine. Just skip the one that's missing.
  8. Right-click on UpperFilters and choose Rename. Add "-BAD" to the end so the entry is named UpperFilters-BAD
  9. Repeat step 8 with the LowerFilters value.
  10. Close Registry Editor and restart your computer.
  11. Check to see if renaming the UpperFilters and/or LowerFilters registry values solved your problem.
  12. If this did not solve you problem, repeat steps 8 and 9 above to return the UpperFilters and LowerFilters values to their original names (without "-BAD" at the end).

It may be necessary to reinstall any programs designed to utilize the device you've removed the UpperFilters and LowerFilters values for. For example you may have to reinstall your DVD burning software.

share|improve this answer

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .