Partition Manager (partmgr) Service Defaults in Windows 8

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

The Partition Manager service is a kernel device driver. In Windows 8 it is being loaded by Boot Loader before Kernel initialization. If Partition Manager fails to load or initialize, the error details should be automatically logged. Then Windows 8 is restarting the PC and attempting to use the Last Known Good configuration. If the Last Known Good configuration isn't working properly, Windows 8 startup ends with a Stop error. If you disable the partmgr service, Windows 8 will fail to start.

Restore Default Startup Configuration for Partition Manager

1. Select your Windows 8 edition and update pack, and then click Download.

2. Save the Win8_partmgr_Service_Startup.cmd file to a local storage device.

3. Run the saved file as an administrator.

4. Restart the computer.

The partmgr service is using the partmgr.sys file that is located in the %WinDir%\System32\drivers folder. If the file is corrupted or deleted, you can put it back in there.