USB Mass Storage Driver (USBSTOR) Service Defaults in Windows 7

USB Mass Storage Class Driver by Microsoft Corporation.

Default Settings

Startup type:Manual
Display name:USB Mass Storage Driver
Service name:USBSTOR
Service type:kernel
Error control:normal
Path:%SystemRoot%\system32\DRIVERS\USBSTOR.SYS
Registry key:HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\USBSTOR

Default Behavior

USB Mass Storage Driver is a kernel device driver. In Windows 7 it won't be started if the user doesn't start it. If USB Mass Storage Driver fails to start, Windows 7 attempts to write the failure details into Event Log. Then Windows 7 startup should proceed and the user should be notified that the USBSTOR service is not running because of the error.

Restore Default Startup Configuration of USB Mass Storage Driver

1. Run the Command Prompt as an administrator.

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

sc config USBSTOR start= demand

3. Close the command window and restart the computer.

The USBSTOR service is using the USBSTOR.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.