Partition Manager (partmgr) Service Defaults in Windows 7

Disk class filter driver that auctions out partitions to volume managers.

Default Settings

Startup type: Boot
Display name:Partition Manager
Service name:partmgr
Service type:kernel
Error control:critical
Group:Boot Bus Extender
Registry key:HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\partmgr

Default Behavior

Partition Manager is a kernel device driver. In Windows 7 it is being loaded by Boot Loader before Kernel initialization. If Partition Manager fails to load, Windows 7 attempts to write the error data into Event Log and restart the computer, using the Last Known Good configuration. If the Last Known Good configuration is not valid, Windows 7 startup ends with a Stop error. If you remove or disable the partmgr service, Windows 7 won't start.

Restore Default Startup Configuration of Partition Manager

1. Run the Command Prompt as an administrator.

2. Copy the commands below, paste them into the command window and press ENTER:

sc config partmgr start= boot
sc start partmgr

3. Close the command window and restart the computer.

The partmgr service is using the partmgr.sys file that is located in the C:\Windows\System32\drivers directory. If the file is removed or corrupted, read this article to restore its original version from Windows 7 installation media.