Partition driver (partmgr) Service Defaults in Windows 10

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

Default Settings

Startup type: Boot
Display name:Partition driver
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 driver is a kernel device driver. In Windows 10 it is starting by the operating system Boot Loader as a part of the driver stack for the boot volume. If Partition driver fails to load or initialize, Windows 10 attempts to record the error details into Event Log and restart the PC, using the Last Known Good configuration. If the Last Known Good configuration cannot be applied or working improperly, Windows 10 startup process halts with a Stop error. If you disable or delete the partmgr service, Windows 10 won't start.

Restore Default Startup Configuration of Partition driver

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 10 installation media.