SCCM 2007 Task Sequence Fails, Drive Letter Not Displayed

Here's an interesting issue I ran into the other day where a Task Sequence would fail in a very bizarre way.  Turns out it was caused by a missing Registry key that caused Partition Manager (PartMgr) to fail to load and start.


1. When a Task Sequence is advertised by SCCM 2007, the Task Sequence fails.  The SMSTS.log file may contain entries similar to the following:

User did not specify local data drive
DeviceIoControl() failed with GetLastError() = 1
CVolume::GetVolumeDiskExtents(volumeHandle, baExtents), HRESULT=80070001 (e:\nts_sms_fre\sms\framework\tscore\diskvolume.cpp,1206)
Ignoring inaccessible volume 'C:'
Volume D:\ is not a fixed hard drive
TSM root drive =
We do not find an available volume to store the local data path

2. When looking at the C: drive in Logical Disk Manager, no drive letter is displayed for the boot drive.  The file system will be shown, and everything else will look normal. Diskpart list volume will not show the drive letter for the boot drive.   A drive letter can be assigned using Diskpart, but even after assigning it, it will not be displayed. WMI, Mountvol, and Windows Explorer will all show the letter C: attached to the boot drive as expected.

This was caused because "UpperFilters" (entry with data value of PartMgr) is missing from HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E967-E325-11CE-BFC1-08002BE10318}

1) Open Regedit
2) Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E967-E325-11CE-BFC1-08002BE10318}.  
3) From the Edit menu, choose New, then ‘Multi-String value’.  
4) Type in "UpperFilters"  (without the quotes) for the value, then hit Enter. 
5) Double click the new UpperFilters entry to open the Edit Multi-String window.
6) In the Value data section, type in "PartMgr"  (without the quotes), and click OK.
7) Reboot the machine

The weird thing is that you could potentially have a missing registry entry for years but never know it until your Task Sequence unexpectedly fails.

For more information on this registry key see

Rich Pesenko

Comments (2)

  1. Anonymous says:

    ERROR 9804 – Memory MB of memory is insufficient. At least Memory MB of memory is required.

    Allocate some more memory.

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