Here's how to prevent Automatic Update from rebooting your machine:
1.Click: Start -> Run
3.Expand: Local Computer Policy / Computer Configuration / Administrative Templates / Windows Components / Windows Update
4.Double-click "No auto-restart for scheduled Automatic Updates installations"
5.Select "Enabled", then OK. Close the Group Policy configuration program.
Please Note the following:
1.You need Administrator priveleges to make this setting.
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