Third Shelf

For the second time now I have had the CD-ROM drive on my HP nw8440 disappear from Windows. The Device Manager reports the following for the CD-ROM drive: “Windows cannot load the device driver for this hardware. The driver may be corrupted or missing. (Code 39)”. Why? It was perfect yesterday and today it is missing or corrupted? Weird. According to the Microsoft Knowledge Base article it can happen after removing a CD or DVD burning program.

Although the error is rather annoying, there is a simple fix for it. I have replicated the steps here for your convenience:

Step 1: Start Registry Editor

Start Registry Editor.

Step 2: Delete the UpperFilters registry entry

1. In Registry Editor, expand My Computer, and then expand HKEY_LOCAL_MACHINE.
2. Expand SYSTEM, and then expand CurrentControlSet.
3. Expand Control, and then expand Class.
4. Under Class, click {4D36E965-E325-11CE-BFC1-08002BE10318}.
5. In the details pane of Registry Editor, on the right side, click UpperFilters.Note You may also see an UpperFilters.bak registry entry. You do not have to remove that entry. Click UpperFilters only.
   • If you see the UpperFilters registry entry in the details pane of Registry Editor, go to step 6.
   • If you do not see the UpperFilters registry entry, you still might have to remove the LowerFilters registry entry. To do this, go to “Step 3: Delete the LowerFilters registry entry.”
6. On the Edit menu, click Delete.
7. Click Yes when you receive the following message:

   Are you sure you want to delete this value?

The UpperFilters registry entry is removed.

Step 3: Delete the LowerFilters registry entry

1. In the details pane of Registry Editor, on the right side, click LowerFilters.Note You might see a LowerFilters.bak registry entry. You do not have to remove that entry. Click LowerFilters only.

   If you do not see the LowerFilters registry entry, unfortunately this content is unable to help you any more. Go to the “Next Steps” section for information about how you can find more solutions or more help on the Microsoft Web site.

2. On the Edit menu, click Delete.
3. Click Yes when you receive the following message:

   Are you sure you want to delete this value?

   The LowerFilters registry entry is removed.

4. Exit Registry Editor.

The article recomends restarting the computer after deleting the two registry entries, but I have found that it works fine without restarting.