Trigw3

Q: Mac mini restarts during boot up

I have a 2012 Mac mini that restarts halfway through booting up. The restarts began while the mini was in sleep mode and required a force quit to make it stop. Now the mini will begin to boot but when the progress bar  is about half way filled the screen goes white for about 15-20 seconds, then goes black for a few more seconds and then the mini attempts a restart.

I have unplugged the power cord, but that did not help. I have also tried holding the command and 'd' keys down during boot but nothing changes.

Thanks in advance for any help.

Mac mini, iOS 9

Posted on Feb 24, 2016 11:12 AM

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Q: Mac mini restarts during boot up

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  • by lllaass,Helpful

    lllaass lllaass Feb 24, 2016 6:05 PM in response to Trigw3
    Level 10 (189,522 points)
    Desktops
    Feb 24, 2016 6:05 PM in response to Trigw3

    - Try resetting the SMC and NVRAM/PRAM

    Intel-based Macs: Resetting the System Management Controller (SMC)

    About NVRAM and PRAM       

    - Try starting in Safe Mode

    OS X: What is Safe Boot, Safe Mode?

    - Boot to Recovery and repair the startup disk

    OS X: About OS X Recovery - Apple Support

    - If it is repairable reinstall the OSX

    How to reinstall OS X on your Mac - Apple Support

    - If you do not have a backup use disk utility to restore the internal disk to an external disk so you can try to recover data.

    Then format the startup disk and do a fresh install of OSX

  • by Linc Davis,Helpful

    Linc Davis Linc Davis Feb 24, 2016 6:05 PM in response to Trigw3
    Level 10 (208,000 points)
    Applications
    Feb 24, 2016 6:05 PM in response to Trigw3

    If you can't start up and log in in the usual way, please try in safe mode.

    During startup, you’ll see a progress bar, and then the login screen, which appears even if you normally log in automatically. You must know your login password in order to log in. If you’ve forgotten the password, you will need to reset it before you begin.

    Log in as an administrator to carry out these instructions. If you have only one account, you are the administrator.

    If you don't see any reports listed, but you know there was a panic, you may have chosen Diagnostic and Usage Messages from the log list. Choose DIAGNOSTIC AND USAGE INFORMATION instead.

    Safe mode is slower than normal, and some things won’t work at all.

    Note: If FileVault is enabled in OS X 10.9 or earlier, or if a firmware password is set, or if the startup volume is a software RAID, you can’t start in safe mode.

    If you're able to log in, launch the Console application in any one of the following ways:

    ☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)

    ☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.

    ☞ Open LaunchPad and start typing the name.

    In the Console window, select

              DIAGNOSTIC AND USAGE INFORMATION ▹ System Diagnostic Reports

    (not Diagnostic and Usage Messages) from the log list on the left. If you don't see that list, select

              View ▹ Show Log List

    from the menu bar.

    There is a disclosure triangle to the left of the list item. If the triangle is pointing to the right, click it so that it points down. You'll see a list of reports. A panic report has a name that begins with "Kernel" and ends in ".panic". Select the most recent one. The contents of the report will appear on the right. Use copy and paste to post the entire contents—the text, not a screenshot.

    I know the report is long, maybe several hundred lines. Please post all of it anyway.

    If you don't see any reports listed, but you know there was a panic, you may have chosen Diagnostic and Usage Messages from the log list. Choose DIAGNOSTIC AND USAGE INFORMATION instead.

    In the interest of privacy, I suggest that, before posting, you edit out the “Anonymous UUID,” a long string of letters, numbers, and dashes in the header of the report, if it’s present (it may not be.)

    Please don’t post other kinds of diagnostic report.

    When you post the report, you might see an error message on the web page: "You have included content in your post that is not permitted," or "The message contains invalid characters." That's a bug in the forum software. Please post the text on Pastebin, then post a link here to the page you created.

    If you have an account on Pastebin, please don't select Private from the Paste Exposure menu on the page, because then no one but you will be able to see it.

  • by Trigw3,

    Trigw3 Trigw3 Feb 24, 2016 6:15 PM in response to Trigw3
    Level 1 (0 points)
    Feb 24, 2016 6:15 PM in response to Trigw3

    I tried starting the mini in safe mode. The progress bar began to fill but then went to a white screen.  The screen has now been white for over an hour. Has my disk died?

  • by Linc Davis,Solvedanswer

    Linc Davis Linc Davis Feb 24, 2016 7:07 PM in response to Trigw3
    Level 10 (208,000 points)
    Applications
    Feb 24, 2016 7:07 PM in response to Trigw3

    Has my disk died?

    Most likely either that or some other hardware fault.

    Make a "Genius" appointment at an Apple Store, or go to another authorized service provider. You may have to leave the machine there for several days.

    Back up all data on the internal drive(s) before you hand over your computer to anyone. There are ways to back up a computer that isn't fully functional—ask if you need guidance.

    If privacy is a concern, erase the data partition(s) with the option to write zeros* (do this only if you have at least two complete, independent backups, and you know how to restore to an empty drive from any of them.) Don’t erase the recovery partition, if present.

    Keeping your confidential data secure during hardware repair

    Apple also recommends that you deauthorize a device in the iTunes Store before having it serviced.

    *An SSD doesn't need to be zeroed.