My computer turned itself on. Was I hacked?

I woke up and found my PC switched on. I have wake on LAN enabled.

I check the log and my pc started up an hour after i went to bed. I have very basic windows log reading skills. Is there something I can check to see if something malicious was done? Im going to change passwords and run virus scan. Incidentally my wifes user account on PC has no password. And she has admin rights.

I know this all sounds bad, but I never expected someone could do anything to me. Also yesterday found out my hotmail account was blocked because of spam sent from my email. I have a very strong password on it to and never use third party hotmail checkers.

Update: i use windows 7 pro

Update: I will read the logs more later, but just so you know Im pretty sure it wasnt a scheduled wake, cause i never leave the PC on overnight, and its the first time this has happened since building this machine 10 months ago. I will of course double check.

Calm down

It is very unlikely that someone has remotely turned on your computer.

Wake On Lan (WOL), as the name implies, will only work on a LAN. Which means, it won't work over the internet.
This is due to how WOL works. The packets that are sent to wake up a computer aren't forwarded by routers. So, the packets will never travel very far (and especially not over the internet).

OK, so what was it?

This still leaves the question, why was the computer even turned on?

Assuming you're using Windows, there are many way a system can be woken up. Let's have a look into Device Manager:

As you can see, many devices can be allowed to wake the computer up. Like a mouse or a keyboard or a network adapter.

So, if your computer was sleeping and someone (maybe a pet) accidentally touched the keyboard, that can already be enough. But there's more!

You might have a scheduled task (maybe a backup) that is allowed to wake your computer so that it can perform.

What woke up the computer?

• Why does my computer keep switching on?

Somewhere in the Event Log, it should say if one of those things started your computer. Sadly, I currently lack a proper entry to provide a good screenshot.

But there are many reasons a computer can wake up from sleep that are far from a hack.

To determine why your computer last woke up from sleep, use powercfg:

powercfg -lastwake