iMac switched itself off?

[glvr]

I left my mac running and camem back a couple hours later to find it switched off.

Assuming that nobody did this manually, or there's been a power interupt, i'm wondering why?

I'm wondering if there's any logs that'll help - but I don't know what to look for.

Console shows approx 5 mins of the same message '8/11/12 09:59:17.897 com.apple.launchd: (IDriveDaemon[24078]) Exited with code: 1', but I don't see how that would have shut it down.

[chabig]

Here are a few thoughts:

1. The console message you quoted means nothing, as it's dated August 11th and today is November 8th.

2. Take a look at your sleep settings in the energy saver preference pane. Maybe your Mac was just asleep.

3. If it was indeed shut down, that can also be set in the energy saver prefpane by clicking the Schedule button. Maybe someone changed your settings.

4. If none of those apply, then maybe your power was interrupted.

[DeltaMac]

8/11/12 may correctly be Nov 8 2012 - depending on your country.
Not everyone uses US English

[glvr]

Thanks, both.

1 Yeah, the date is right.

2 It was definitely off, not asleep.

3 The schedule is unchanged.

4 That's where I came in, and it's probably the cause but I wanted to be surer and that's why I posted.

[chabig]

Delta, you're probably right. I should've thought of that.

[NovaScotian]

I have a 27" iMac (Mid 2011) that occasionally turns itself off. So far as I can determine, it is caused by a power glitch. If the power goes off for long, the machine restarts when it comes back on and leaves a console note, but if the power is off for and undetermined short time, less that a second, the machine stays off. Don't know why; I just push the power button and away we go. It also happens occasionally that the machine is asleep, but neither keyboard nor mouse will wake it up -- in that case, the power button does, but I'm in the desktop immediately, not starting up. Again, don't know why.