Mac Mini auto restarts when shutting down with Mountain Lion

I don't think it has anything to do with Mountain Lion, or at least is not unique to ML. My MacMini (server) does the same thing which is annoying sometimes, i.e having to shut it down twice in a row. I'm running Lion Server on my Mac Mini. I haven't tested it out yet but I have a feeling it might have something to do with the fact that I have the shutdown and startup of my Mac Minin on a schedule. Again, I haven't confirmed this by disabling the shutdown/startup schedule so it's just a guess at this point so I could be totally off regarding that. But it's definitely not unique to the Mac Mini running Mountain Lion.

Exactly same problem after updating.

Thanks for posting. I just installed a mountain lion update to my mac mini and now I am stuck in this endless shutdown the computer tells me there's a problem, and then it restarts itself. It keeps saying I am shutting down becoause there's a problem even though i am trying to shut down because that's what I ususally do. It thinks I have programs still open. I am glad to see that I am not the only person experiencing this problem.

@applesinafton: Are you saying that the Mini restarts everytime you try to shut it down? In my case, it used to restart just once. Then when I shut it down the second time, it did shut down. If your is always restarting no matter how many times you try to shut it down, then it doesn't seem like the same issue I was experiencing under Lion Server (it's no longer doing that and I'm now running Mountain Lion Server). Hopefully Apple can come up with a fix for your problem soon.

Try the following:

1. Reset the SMC then try shutting down.

2. If that isn't enough, then unplug any non-essential peripherals, i.e. every but monitor, keyboard, and mouse.

If the keyboard and mouse are USB, then plug them separately and directly into the computer; do not pass through a hub be it the one in the keyboard or monitor.

Then try shutting down again.

- Sometimes USB devices can cause what you're seeing, so removing all but the essentials and plugging the keyboard and/or mouse directly into the computer can help to eliminate that -- unless of course either or both are bad. I once had a USB fail, which caused a Mac to reboot continuously.

Thanks everyone for the responses. I tried to forcequit everything and tried resetting my SMC, but nothing worked. The only way that works for my mac mini is if you hold the power button down for 10 seconds, then it shuts down. However, as soon as it starts up, and you try to shut it down again, it goes into that weird restart cycle. I don't know if it makes any difference, but I use apple's bluetooth wireless keyboard and trackpad.

I just hope apple puts out a fix soon, this literally started after I applied the OSX update.

same situation. MacMini 2011. Every time I try to shut down it restarts and than day that something goes wrong during the reboot...

@ Applesinafton, I hope you don't have to unplug the power cord each and every time you want to shut down the mini, or do you? Or did unplugging the power cord fix the problem so that now you can shut down normally without the mini wanting to reboot again?

Same problem here, but after restarting once it shuts down. I have tried all things listed here, but it still does it. I have all the updates and only have apple wireless keyboard, mouse and trackpad so starting is safe mode is hard to do.

Tsofa

New Mac Mini with latest Lion Update.

Tried to unplug the power cord. Nothing changed. Same situation...

Any progress guys? Im having the exact same issue. It has to do with macminis, it cant be a coincidence.