I was surfing for some WSUS scripts today and came across this one by Mohammed. This script is for configuring client machines to use a local WSUS server rather than Windows/Microsoft Update web sites.
I took a few of the registry keys from his script to delay the very annoying “Updating your computer is almost complete. You must restart your computer for the updates to take effect. Do you want to restart your computer now?” messages that pop up every five minutes or so, along with the automatic reboot that occurs ten minutes after the updates are applied.
Windows Registry Editor Version 5.00
Save the blue text above in a text editor and name it nonag.reg, then double click nonag.reg to import it into the registry. Although this will not stop the reboot notices entirely, it will only show the message once every 24 hours, and it will not automatically reboot itselt as long as someone is logged into the machine.
Note that you can stop the nag screens totally by disabling the Automatic Updates service.
You can also use Group Policy to distribute these settings to clients. To use Windows local policies, goto Computer Configuration -> Administrative Template -> Windows Components -> Windows Update – Double click on No auto-restart for scheduled Automatic Updates installations and select enabled. Reboot or run gpupdate /force for the changes to take effect.