Won't boot into safe mode

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Level 1

8 points

Won't boot into safe mode

My 2012 iMac 27" was randomly rebooting itself, while in Sleep. I assumed this was due to the cheap 32 GB memory I bought, but before I could change it back to the original memory, to test, the Mac booted into Safe Mode (I assume - a progress bar showing at the bottom of the boot screen, below the Apple logo), and did not get further than a half the way, and then shut down. I swapped the memory to the original 8GB. I tried booting again, no buttons held down, as then it wouldn't get further than a quarter of the way. Further attempts to boot do not work, even when holding down Option to choose the boot disk, pressing Shift for Safe Mode, or Option-S for Single User Mode. I assume it's trying to boot in Safe Mode, but failing?

I also tried using a good Mac with the bad Mac as the Target Disk boot mode - the good Mac does not see the bad Mac...

I have an external DVD drive, but that isn't an option as I can't go into boot drive select mode. What are my options, apart from sending the iMac back?

iMac, OS X Mountain Lion (10.8.2), 2012 iMac 27" 3.2GHz i5

Posted on Jan 26, 2013 11:50 AM

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Answer 1

Paul_31

Level 6

14,160 points

Jan 26, 2013 12:21 PM in response to andrew_cw

Have you tried an SMC and PRAM Reset? Might help:

https://discussions.apple.com/docs/DOC-3603

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Answer 2

andrew_cw Author

Level 1

8 points

Jan 26, 2013 12:32 PM in response to Paul_31

Thanks Paul, but I tried these and they don't help.

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Answer 3

Paul_31

Level 6

14,160 points

Jan 26, 2013 12:37 PM in response to andrew_cw

Have you tried booting into the Recovery HD - restart holding Command+r and at the screen with four choices (hopefully you get this far) select Disk Utility>Macintosh HD and click on repair disk. If it makes any changes click repair disk again until you get a clean pass and then start normally from the Apple menu.

If this doesn't work and you have a DVD boot disk try restarting with it in the DVD drive whilst holding down the 'c' key. Hopefully that'll allow you to run repairs from Utilities>Disk Utility.

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Answer 4

andrew_cw Author

Level 1

8 points

Jan 26, 2013 12:37 PM in response to andrew_cw

A correction to my original post: I forgot I can select the boot drive when holding down Option. However it didn't show the OS X install disk. It showed my Boot Camp partition, and Windows runs fine. This means at least my hardware is OK for Windows, and the Windows partition works.

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Answer 5

andrew_cw Author

Level 1

8 points

Jan 26, 2013 12:54 PM in response to Paul_31

OK, I tried the Command-R thing and Verified the disk - there are problems and it need to be Repaired. I can't select Repair (I assume because it's the disk I booted from), so I booted from a Snow Leopard DVD install disk (using C key, not Options key as I mistakingly assumed). But, that creates a 'panic' screen with a lot of unintelligable system information in the top left, and a message telling me to switch off in the middle...

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Answer 6

Paul_31

Level 6

14,160 points

Jan 26, 2013 1:07 PM in response to andrew_cw

Booting into the Recovery HD should allow you to effect repairs - that's the point of it, so it's a bit concerning that it won't allow you to. The Recovery HD is a partition on the internal drive that should allow you to effect repairs to the Macintosh HD, albeit part of the same physical disk.

I'm no expert, but I'd be concerned that the hard disk is on the way out. Do you have backup of everything - Time Machine or a bootable clone, perhaps?

Maybe have another try with Command+r. If it fails I'm not sure what would be the best next step - it depends if you have a full and up-to-date backup of your disk so that you can restore.

One of the options of the Recovery HD is to allow you to re-install the OS, which won't delete your data.

The more extreme step would be Internet Recovery which would involve erasing everything and re-installing via the internet.

Worth reading this carefully before proceeding: http://support.apple.com/kb/HT4718

Disk Warrior from Alsoft (not cheap) is another possibility for recovering damaged disks, although it's not a guaranteed solution.

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Answer 7

baltwo

Level 9

62,362 points

Jan 26, 2013 2:49 PM in response to andrew_cw

andrew_cw wrote:

OK, I tried the Command-R thing and Verified the disk - there are problems and it need to be Repaired. I can't select Repair (I assume because it's the disk I booted from), so I booted from a Snow Leopard DVD install disk (using C key, not Options key as I mistakingly assumed). But, that creates a 'panic' screen with a lot of unintelligable system information in the top left, and a message telling me to switch off in the middle...

AFAIK, your machine cannot boot with a Snow Leopard install disc. IMO, best thing to do is contact Apple's Express Lane and let them deal with this new machine. Do note that if you have AppleCare's protection plan and you're within 50 miles (80 KM) of an Apple repair station, you might be eligible for onsite repair since yours is a desktop machine (depends on where you're located).

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Answer 8

andrew_cw Author

Level 1

8 points

Jan 27, 2013 3:31 AM in response to baltwo

I wasn't able to re-install the OS from the Recovery HD, as it gave an error, so I decided to erase the drive and re-install. I have backups from my old Snow Leopard machine, but I'm going to use Migration Assistant. I haven't lost any data.

I'll use the origanal RAM for a while, then install the 3rd party RAM to see if the same rebooting problem happens. If so, I'll religiously verify and repair the disk as needed, and send the RAM back.

Thanks for the help guys.

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Answer 9

Paul_31

Level 6

14,160 points

Jan 27, 2013 3:33 AM in response to andrew_cw

Good luck - let us know how it turns out and whether the RAM is the culprit.

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