Common Log (CLFS) Service Defaults in Windows 10

General-purpose logging service.

Default Settings

Startup type:Boot
Display name:Common Log (CLFS)
Service name:CLFS
Service type:kernel
Error control:critical
Registry key:HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\CLFS

Default Behavior

Common Log (CLFS) 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 Common Log (CLFS) 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 CLFS service, Windows 10 won't start.

Restore Default Startup Configuration of Common Log (CLFS)

1. Run the Command Prompt as an administrator.

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

sc config CLFS start= boot
sc start CLFS

3. Close the command window and restart the computer.

The CLFS service is using the CLFS.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.