Reboots and Automatic Updates

I couldn't check last week, as I was out of the office sick, but someone had asked if anyone's system had done an uncommanded reboot in response to automatic updates.

I thought I'd go through my workstation's event log, and I've found a two interesting log entries, so far:

Installation Ready: The following updates are downloaded and ready for installation. This computer is currently scheduled to install these updates on ‎Wednesday, ‎December ‎09, ‎2009 at 3:00 AM: - Windows Malicious Software Removal Tool x64 - December 2009 (KB890830)
and

Installation Ready: The following updates are downloaded and ready for installation. This computer is currently scheduled to install these updates on ‎Wednesday, ‎December ‎09, ‎2009 at 3:00 AM: - Cumulative Security Update for Internet Explorer 8 for Windows 7 for x64-based Systems (KB976325) - Windows Malicious Software Removal Tool x64 - December 2009 (KB890830)

Now, I have Windows set up to download only. It's supposed to wait for my confirmation before I install. Notice that those two events include the phrase, "This computer is currently scheduled to install these updates on Wednesday, December 09, 2009 at 3:00AM" ... I didn't tell Windows it could do that. Or, at least, that's not what the normal interface indicated it was set up to do. (I don't make a habit of digging through Administration Tools and tweaking things, as I don't know the full impact of most of what's in there.)

Without finding the setting that automatically schedules updates for next-day installs, even when you tell it to download and wait for confirmation, the only obvious solution is

The only solution to uncommanded reboots, as far as I can see, is to tell it to not even download the updates unless instructed. Not as convenient as having it download in the background, but it saves you the hassle of having a machine reboot on its own, leaving you scratching your head as to why.

Update

Ok, something reset my Windows Update preferences. I just checked again, and it was set to "Install Automatically."