Saturday morning, before going out with my family on a shopping tour I started a large FTP download and assumed it would have completed upon my return…. a few hours later, I found my system at the logon prompt, as it had rebooted itself automatically and of course the FTP download was not completed.
What happened ? Very simple, Windows Update had automatically rebooted the system, probably after having displayed a message as shown in the screen shot below.
Was it really Windows Update ? Yes, i compared the time the FTP transfer had stopped with the Event log entries and the time period seemed to match.
To prevent Windows Update from automatically rebooting in the future, I applied the following Windows registry keys::
