:Check for residual disk driver entries in the Windows registry

Problem description

• A disk attached to a Windows instance in the ECS console is not recognized.

• A disk attached to a Windows instance is inaccessible.

Cause

Residual disk driver entries exist in the Windows registry.

Solution

1. Connect to the Windows instance.

   See Choose a connection method.

2. Open Registry Editor.

   1. Enter Registry Editor in the Windows search box.

   2. Click Registry Editor in the search results.

      Registry Editor opens.

3. Go to HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4d36e967-e325-11ce-bfc1-08002be10318} and check the UpperFilters parameter.

   • Right-click UpperFilters and select Modify. If Value data contains only partmgr, no residual entries exist.

   • Right-click UpperFilters and select Modify. If Value data contains fields other than partmgr, residual entries exist. For example, a test_filter field in Value data indicates a residual entry:

4. Go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\SCSI and check each disk for residual driver entries.

   • If a disk has no UpperFilters parameter, no residual driver entries exist for that disk.

   • If a disk has the UpperFilters parameter, residual driver entries exist.

     The disk driver under Disk drives becomes abnormal and the disk is inaccessible:

5. Delete the residual entries.

   1. Go to HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4d36e967-e325-11ce-bfc1-08002be10318}.

   2. Right-click UpperFilters and select Modify. Delete the residual fields from Value data, such as test_filter.

      Warning

      Only delete fields whose corresponding drivers have been uninstalled. Deleting fields for in-use drivers makes them unusable. To verify, check whether the driver file exists in C:\Windows\System32\drivers, such as test_filter.

      

   3. Click OK.

6. Restart the instance.

   See Restart an instance.

   Warning

   The restart operation stops the instance for a short period of time and may interrupt services that are running on the instance. We recommend that you restart the instance during off-peak hours.