QoS Packet Scheduler (Psched) Service Defaults in Windows 7

QoS Packet Scheduler.

Default Settings

Startup type: System
Display name:QoS Packet Scheduler
Service name:Psched
Service type:kernel
Error control:normal
Registry key:HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Psched

Default Behavior

QoS Packet Scheduler is a kernel device driver. In Windows 7 it is being loaded at Kernel initialization. If QoS Packet Scheduler 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 Psched service is not running because of the error.


If QoS Packet Scheduler is stopped, the Quality Windows Audio Video Experience service fails to start and initialize.

Restore Default Startup Configuration of QoS Packet Scheduler

1. Run the Command Prompt as an administrator.

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

sc config Psched start= system
sc start Psched

3. Close the command window and restart the computer.

The Psched service is using the pacer.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.