This article explains how to delete the UpperFilters and LowerFilters values in the Windows Registry. The same steps apply no matter which version of Windows you’re using, including Windows 11, 10, 8, 7, Vista, and XP.

What to Know

  • Open Registry Editor and go to HKEY_LOCAL_MACHINE > System > CurrentControlSet > Control > Class.
  • Determine the Class GUID for the hardware device that you’re seeing the error code for, then select the corresponding subkey.
  • Right-click UpperFilters and LowerFilters, and select Delete and Yes to confirm.

How to Delete the UpperFilters and LowerFilters Registry Values

Removing the UpperFilters and LowerFilters values in the Windows Registry is easy and should take less than 10 minutes:

  • Execute regedit from the Run dialog box (WIN+R) or Command Prompt to open Registry Editor.
  • Changes to the registry are made in these steps! Take care to only make the changes outlined below. We highly recommend that you play it safe by backing up the registry keys you plan on modifying.
  • If you’re using Windows 11, 10, 8, 7, or Vista, you may need to answer Yes to any User Account Control questions before Registry Editor will open.
  • Locate the HKEY_LOCAL_MACHINE hive on the left side of Registry Editor and then tap or click the > or + icon next to the folder name to expand it.
  • Continue to expand the “folders” until you reach this registry key.
  • HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class
  • Tap or 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 looks something like this:
  • {4D36E965-E325-11CE-BFC1-08002BE10318}
  • Class Key Expanded in Registry Editor.
  • Each 32-digit subkey is unique and corresponds to a particular type, or class, of hardware in Device Manager.
  • Determine the correct Class GUID for the hardware device. Using this list, find the correct Class GUID corresponding to the type of hardware that you’re seeing the Device Manager error code for.
  • For example, let’s say your DVD drive is showing a Code 39 error in Device Manager. According to the list above, this is the GUID for CD/DVD devices:
  • 4D36E965-E325-11CE-BFC1-08002BE10318
  • Once you know this GUID, you can continue with Step 6.
  • Many of these GUIDs look the same but they’re definitely not. They are all unique. It might help to know that in many cases, the difference from GUID to GUID is in the first set of numbers and letters, not the last.
  • Select the registry subkey corresponding to the device’s Class GUID that you determined in the last step.
  • In the results that appear on the window on the right, locate the UpperFilters and LowerFilters values.
  • If you don’t see either value listed, this solution isn’t for you. Double-check that you’re looking at the correct device class, but if you’re sure you are, you’ll have to try a different solution from our How to Fix Device Manager Error Codes guide.
  • If you only see one or the other value, that’s fine. Just complete Step 8 or Step 9 below.
  • Right-click or tap-and-hold on UpperFilters and choose Delete. Choose Yes to the “Deleting certain registry values could cause system instability. Are you sure you want to permanently delete this value?” question.
  • You might also see an UpperFilters.bak or LowerFilters.bak value but you don’t need to delete either of these. Deleting them probably won’t hurt anything but neither one is causing the Device Manager error code you’re seeing.
  • Repeat Step 8 with the LowerFilters value.
  • Verify that neither an UpperFilters nor a LowerFilters registry value exists, and then close Registry Editor.
  • Restart your computer.
  • Check to see if deleting these registry values solved your problem.
  • If you’ve completed these steps due to a Device Manager error code, you can view the device’s status to see if the error code is gone. If you’re here because of a missing DVD or CD drive, check This PC, Computer, or My Computer, and see if your drive has reappeared.
  • It may be necessary to reinstall any programs designed to utilize the device you’ve removed the UpperFilters and LowerFilters values for. For example, if you removed these values for the BD/DVD/CD device, you may have to reinstall your disc burning software.

When to Delete the UpperFilters and LowerFilters Registry Values

Removing the UpperFilters and LowerFilters registry values is a likely solution to a number of Device Manager error codes.

As you’ll see below, deleting registry data is a pretty straightforward concept, but if you’re not comfortable with it, learn how to add, change, & delete registry keys & values in the Windows Registry Editor.

Execute regedit from the Run dialog box (WIN+R) or Command Prompt to open Registry Editor.

Changes to the registry are made in these steps! Take care to only make the changes outlined below. We highly recommend that you play it safe by backing up the registry keys you plan on modifying.

If you’re using Windows 11, 10, 8, 7, or Vista, you may need to answer Yes to any User Account Control questions before Registry Editor will open.

Locate the HKEY_LOCAL_MACHINE hive on the left side of Registry Editor and then tap or click the > or + icon next to the folder name to expand it.

Continue to expand the “folders” until you reach this registry key.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class 

Tap or 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 looks something like this:

{4D36E965-E325-11CE-BFC1-08002BE10318}

Each 32-digit subkey is unique and corresponds to a particular type, or class, of hardware in Device Manager.

Determine the correct Class GUID for the hardware device. Using this list, find the correct Class GUID corresponding to the type of hardware that you’re seeing the Device Manager error code for.

For example, let’s say your DVD drive is showing a Code 39 error in Device Manager. According to the list above, this is the GUID for CD/DVD devices:

4D36E965-E325-11CE-BFC1-08002BE10318

Once you know this GUID, you can continue with Step 6.

Many of these GUIDs look the same but they’re definitely not. They are all unique. It might help to know that in many cases, the difference from GUID to GUID is in the first set of numbers and letters, not the last.

Select the registry subkey corresponding to the device’s Class GUID that you determined in the last step.

In the results that appear on the window on the right, locate the UpperFilters and LowerFilters values.

If you don’t see either value listed, this solution isn’t for you. Double-check that you’re looking at the correct device class, but if you’re sure you are, you’ll have to try a different solution from our How to Fix Device Manager Error Codes guide.

If you only see one or the other value, that’s fine. Just complete Step 8 or Step 9 below.

Right-click or tap-and-hold on UpperFilters and choose Delete. Choose Yes to the “Deleting certain registry values could cause system instability. Are you sure you want to permanently delete this value?” question.

You might also see an UpperFilters.bak or LowerFilters.bak value but you don’t need to delete either of these. Deleting them probably won’t hurt anything but neither one is causing the Device Manager error code you’re seeing.

Repeat Step 8 with the LowerFilters value.

Verify that neither an UpperFilters nor a LowerFilters registry value exists, and then close Registry Editor.

Restart your computer.

Check to see if deleting these registry values solved your problem.

If you’ve completed these steps due to a Device Manager error code, you can view the device’s status to see if the error code is gone. If you’re here because of a missing DVD or CD drive, check This PC, Computer, or My Computer, and see if your drive has reappeared.

It may be necessary to reinstall any programs designed to utilize the device you’ve removed the UpperFilters and LowerFilters values for. For example, if you removed these values for the BD/DVD/CD device, you may have to reinstall your disc burning software.

These values, sometimes incorrectly called “upper and lower filters,” might exist for several device classes in the registry, but those values in the DVD/CD-ROM Drives class tend to corrupt and cause problems most often.

A few of the more common Device Manager error codes that are frequently caused by UpperFilters and LowerFilters issues include Code 19, Code 31, Code 32, Code 37, Code 39, and Code 41.

More Help With the UpperFilters and LowerFilters Registry Values

If you still have a yellow exclamation mark in Device Manager even after following the above steps, head back to our troubleshooting information for your error code and look into some other ideas. Most Device Manager error codes have several possible solutions.

  • What if I delete the wrong UpperFilters?
  • If you delete UpperFilters and it causes problems with your computer, reinstall any software related to the hardware device you’re having issues with. If you still have problems, try performing a clean install of Windows or a Windows System Restore.
  • What should my keyboard UpperFilter be?
  • The UpperFilter for keyboards is typically kbdclass. The GUID is4D36-E96B-E325-11CE-BFC1-0800-2BE1-0318.
  • How do I restore UpperFilters and LowerFilters?
  • If you have a backup, restore the Windows Registry. Otherwise, reinstall any software related to the hardware device, or perform a System Restore.

If you delete UpperFilters and it causes problems with your computer, reinstall any software related to the hardware device you’re having issues with. If you still have problems, try performing a clean install of Windows or a Windows System Restore.

The UpperFilter for keyboards is typically kbdclass. The GUID is

If you have a backup, restore the Windows Registry. Otherwise, reinstall any software related to the hardware device, or perform a System Restore.

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