Finding the cause why a laptop wakes itself from sleep

Question

My new Windows 7 64bit laptop keeps waking up from sleep. I tried various things and still it wakes up:

• Disconnecting the mouse\keyboard
• Disconnecting it from the LAN
• Keeping it with the lid closed

How can I find the reason for its wakeup?

Answer 1

• Take a look at the Event Log
• Check if there are scheduled tasks

Answer 2

Is your network card allowed to wake the computer?

1. Open Device Manager
2. Open Network Adapters and navigate to your network card.
3. Right click on the network card and select properties.
4. Go to the Power Management tab and untick the option to prevent your network card from waking up Windows.

A few commands to see what the last wakeup events were, and which device caused it:

powercfg -lastwake
powercfg -devicequery wake_armed

Also check in Control Panel:

• Power Settings, Change Plan Settings, Change Advanced Power Settings

... walk the list there and see if anything looks promising.