I have a laptop which has "recently" turned into the proverbial baby, and refuses to sleep through the night, or for that matter, through some days. I'm a little lost when it comes to trying to debug what is causing it to wake for no apparent reason.
EDIT:
Powercfg tells me:
C:\>powercfg -lastwake
Wake History Count - 1
Wake History [0]
Wake Source Count - 1
Wake Source [0]
Type: Fixed Feature
Timer Expired (RTC)
So it appears something is set an alert to wake the system up? But how would I find out what?
You can use the PowerCfg utility to find out. It's part of Vista, no need to download it.
Will tell you what woke up your laptop.
To see all devices that can wake your computer, try:
You can turn all these devices off with Device Manager, on the Power Management tab. Unselect "Allow this device to wake up the computer".
Tracked it down to be Windows Media Centre downloading the TV guide every four hours or so -- disabling that now lets the poor laptop sleep for as long as it likes.
Things to check:
Check its not related to your "Wake On Pattern Match" network adapter settings. Similar to wake-on-lan this setting can cause the network adaptor to wake up from unexpected things like ARP and NetBios over TCP (NBT) broadcasts -- which I suspect happen quite a lot on the average network.
For more info check out my blog post about random wake ups.
Not a great solution but have you tried using Hibernate instead of sleep? I'm just wondering if there are more wakeup events that apply to sleep than to hibernate. It might be that only the hardware with wake capabilities applies to Hibernate.
Just a thought...
I have a desktop that does the same thing. I can't be sure, but I swear it is related to keeping the browser open on certain websites. Maybe I'm correlating the wrong information, but it appears that certain websites will cause the desktop into thinking there is user action when it is really just push content from the website.