Partition driver (partmgr) Service Defaults in Windows 11
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 |
| Path: | %SystemRoot%\System32\drivers\partmgr.sys |
| Registry key: | HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\partmgr |
Default Behavior
Partition driver is a kernel driver. In Windows 11 it starts by the operating system Boot Loader before the Kernel initialization, as a part of the driver stack. If Partition driver fails to start, Windows 11 tries to record the error details into Event Log and restart the PC, using the Last Known Good configuration. If the Last Known Good configuration can't be used, Windows 11 startup process halts with a Stop error. If you disable or delete the partmgr service, Windows 11 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 11 installation media.