Mac Mini auto restarts when shutting down with Mountain Lion

No news from apple?

Apple released today EFI update 1.7 just for late 2012 mac mini, not for late 2010...

I do not know if this helps, but I have a Power Mac and have turned off the aut restart in the energey saving control panel. So far I have not had a restart on shut down. Kind of makes a "little sense" as it does contain the word "restart". LOL

I had the same behavior, although my Mac Mini didn't immediately restart until sometime later. Turns out I had inadvertently set an option on a scheduled task within Carbon Copy Cloner to wake or reboot as required before running the task. In the course of determining what the cause of the resrats were, I looked at the Mac terminal log and saw that the time of the last login was approaximately the time of the scheduled task. From there it was a simple matter of finding the hidden parameter in the application. Hope this helps some one out there.

Jeffrey, glad you found a resolution but I do not have any auto scans. Mine just resarts every other shut down. I thought I had solved it but to no avail. Apple, please help.

I am still having this problem too, with a mid 2011 mac mini (nvidia graphics).

I also find my mac mini has restarted on its own or is frozen, randomly.

Problem started with ML and still present, all up to date. Have completely reinstalled too, fresh, using ML DVD created from app store download before installing it.

This problem does not occur, or any others, when using windows 7 via bootcamp. It is always stable and can be left on indefinitely. I'm using as a media centre so it's left on for days, sometimes put to sleep.

I'm connected to a Samsung tv via hdmi through a hdmi detective and onkyo amp. Have tried without intermediate devices and using other tv profiles on the detective, no difference.

Same problem no matter whats plugged in, even just hdmi.

Please recognise and address these issues apple!

Correction, mid 2010! Optical drive, core2duo, nvidia 320M..

I used to run my Mac Mini (2012) with Lion and XBMC under my 32" Samsung TV and never had an issue with shutting it down.

I then upgraded to Moutain Lion via upgrade and moved my Mac mini to my office with my 24" Samsung TV...

Then I noticed my Mac Mini would reboot when I was screen sharing and I tried to shutdown...

This is annoying when you are using it remotely.

So being a techie sort of guy I went overkill and did the follwoing:

- Wiped the HDD

- Did a fresh install of Moutain Lion

- Cleared the NVRAM (Rebooted 10 times)

- Cleared the PRAM (Rebooted 10 times)

The shutdown problem still persisted....

My conclusion was it must have been upgrading the OS from Lion to Mountain Lion however my work colleague (mockingly) pointed out that in the forums someone said is to do with the HDMI.

I ran tests:

24" Samsung TV Powered On - HDMI Connected - Shutdown (Issue occurred)

24" Samsung TV Powered Off - HDMI Connected - Shutdown (Issue did not occur)

(To test this I turned the tv off and watched what I was doing via Screenshare)

24" Samsung TV Powered On - HDMI Connected - Shutdown via Screen Sharing (Issue occurred)

24" Samsung TV Powered Off - HDMI Connected - Shutdown via Screen Sharing (Issue did not occur)

HDMI Disconnected - Shutdown via Screen Sharing (Issue did not occur)

- So I ran further tests!!!!

32" Samsung TV Powered On - HDMI Connected - Shutdown (Issue did not occur)

32" Samsung TV Powered Off - HDMI Connected - Shutdown (Issue did not occur)

(To test this I turned the tv off and watched what I was doing via Screenshare)

32" Samsung TV Powered On - HDMI Connected - Shutdown via Screen Sharing (Issue did not occur)

32" Samsung TV Powered Off - HDMI Connected - Shutdown via Screen Sharing (Issue did not occur)

It looked like it was the 24" TV however whilst I was testing with the 32" TV I got annoyed that the menu bar was off screen so I turned the resolution down from (1920X1080 @60hz) to (1360 x 768 @60hz), shutdown, and on the second shutdown the issue occurred!!!!!

So I checked my 24" TV (1360 x 768 @60hz) was the original resolution.

I have changed it to 1600 x 900 and no shutdown issue on the 24" TV!!!!

So the resolution 1360 x 768 seems to be the problem!!!!!!

I did something similar to willbobaggins (including reformating the HD), but no permament solution.

My experience/impression so far: if i fiddle with the display resolution (preferences => display), then the Mac mini (mid 2010) shuts down properly (ie without restarting). The fiddling can be minimal (ie select other resolution, and set it back to the original resolution), but it works only if done directly on the machine (ie when done via screen sharing the machine will restrart).

I'll keep doing that - and pray that Apple renounces it's "Windows-ways" and a) aknowledges, b) fixes the problem.

Sorry for late reply... Plex media server causes restart for me...if app is closed no restart... Yes to 720p.. Yes to Samsung 51 plasma via hdmi

Whilst waiting for Apple to resolve this issue,to save time from switching the screen resolution before log out and after log in again, I'm using Display Menu from App Store. It's free and easy to use.