To turn off Windows 11 updates in Service Manager, do the following:

1. To launch the Run dialogue, press Win + R.
2. To open the Service Manager, type services.MSC and click OK.
3. Locate the Windows Update service in the Services pane.
4. Select Properties from the context menu when you right-click on the service.
5. Select Disabled from the Startup type drop-down menu.
6. To save the changes, click OK and Apply. To finish the adjustments, restart your computer, and Windows 11 should no longer auto-update.

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