Enables relative prioritization of work based on system-wide task priorities. This is intended mainly for multimedia applications. If this service is stopped, individual tasks resort to their default priority.
This service also exists in Windows 10, 11, 8 and Vista.
Windows 7 edition | without SP | SP1 |
---|---|---|
Starter | Automatic | Automatic |
Home Basic | Automatic | Automatic |
Home Premium | Automatic | Automatic |
Professional | Automatic | Automatic |
Ultimate | Automatic | Automatic |
Enterprise | Automatic | Automatic |
Display name: | Multimedia Class Scheduler |
Service name: | MMCSS |
Type: | share |
Path: | %WinDir%\system32\svchost.exe -k netsvcs |
File: | %WinDir%\system32\mmcss.dll |
Error control: | normal |
Object: | LocalSystem |
Privileges: |
|
The Multimedia Class Scheduler service runs as LocalSystem in a shared process. It shares the executable file with other services. If the Multimedia Class Scheduler fails to load or initialize, the error is recorded into the Event Log. Windows 7 startup should proceed, but a message box is displayed informing you that the MMCSS service has failed to start.
If the Multimedia Class Scheduler is stopped, the Windows Audio fails to start and initialize.
1. Select your Windows 7 edition and Service Pack, and then click on the Download button below.
2. Save the RestoreMultimediaClassSchedulerWindows7.bat file to any folder on your hard drive.
3. Right-click the downloaded batch file and select Run as administrator.
4. Restart the computer to save changes.
Note. Make sure that the mmcss.dll
file exists in the %WinDir%\system32
folder. If this file is missing you can try to restore it from your Windows 7 installation media.