How to tell what woke the computer time before last

[mrochester]

I hibernate my computer at night. On a number of mornings I've woken to find the power LED flashing, which means it is in sleep mode. This means that sometime during the night it has woken, sat idle for 30 minutes, and then automatically gone to sleep. In the morning, I have woken it from sleep again. How do I see what woke the computer up during the night?

Many thanks

Michael.

 

[meths]

A hidden camera with a night-vision lens would do it.

 

[Tomsk]

Look in the Event Viewer. It's buried in computer management/Adminstrative tools.

 

[Waza]

A hidden camera with a night-vision lens would do it.

Lol

 

[mrochester]

Look in the Event Viewer. It's buried in computer management/Adminstrative tools.

That's where I normally look, but it doesn't say exactly what woke the computer. I know there is something you can type into a command prompt that will say exactly which device woke the computer last, but if I do that it'll simply show me clicking the mouse to wake from sleep when I got out of bed, not what woke it in the middle of the night!

3:02am was the first event in the event log, which states:

"The system time has changed to ‎2009‎-‎12‎-‎11T03:02:15.500000000Z from ‎2009‎-‎12‎-‎10T23:02:32.094262300Z."

Then at 3:32am it went to sleep again.

 

[Confused]

3am is the default time for it to check/install Windows Updates.

 

[mrochester]

It doesn't do this every night though, it appears to be random.

 

[malachi]

I have the same problem with my Media Centre PC. Happens when I had Vista and now with Win 7. Randomly wakes up 3 times during the night and goes back the sleep 1 min after. Ive checked all the power saving settings in windows and the bios but never figured out that was causing it.

 

[Fegruson]

Try disabling the Wake On LAN feature in the BIOS? It might be something to do with your router/modem. Or maybe IP leasing times?