Preventing Windows Update From Rebooting

Here's how to prevent Automatic Update from rebooting your machine:

1. Start -> Run
2. Type: gpedit.msc
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.

You can also prevent the dialog asking to reboot from appearing too often by enabling the "Re-prompt for restart with scheduled installations" and set the amount of time to a bigger number than 10 minutes.