Mac can't finish start up

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NickConnolly Author

Level 1

5 points

Mac can't finish start up

My Mac running Mountain Lion can no longer complete start up.

On start up Apple logo and spinning thingy appear as normal but after 30 minutes the Mac is still in the same state.

This is the latest in erratic behaviour after recent OS updates:

1. backing up on Time Machine became inordinately long

2. After about an hours use the system would become increasingly sluggish

Situation has no progressed to Mac not being able to finish start up.

Tried booting in recovery mode and the utilities gave the disks a clear bill of health. Tried a re-install of Mountain Lion from there but the Mac couldn't complete that either.

I'm both puzzled and frustrated now.If it was a hardware issue then why is the startup screen being all happy-mac? If it is the disk then why are the recovery utilities giving them a clean bill of health? I don't know that the recent updates are the problem but the issues coincided with them and the machine has been fine prior.

Intel Mac about 4 years old.

iMac, OS X Mountain Lion (10.8.2)

Posted on Oct 12, 2012 3:40 PM

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Answer 1

John Galt

Level 10

156,626 points

Oct 12, 2012 3:48 PM in response to NickConnolly

It could be that your hard disk is having problems.

Boot while holding the d key and run Apple Hardware Test. Run the extended tests.

Boot OS X Recovery again and run Disk Utility. Repair the disk. Report any errors that it finds.

If you cannot find anything wrong try starting the Mac in Safe Mode.

Read about it first:

Starting the computer in "safe mode": Mac OS X: What is Safe Boot, Safe Mode?

Safe Mode is for troubleshooting only. Startup will take a long time. Some programs will not run in Safe Mode.

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Answer 2

NickConnolly Author

Level 1

5 points

Oct 12, 2012 4:13 PM in response to John Galt

Start up holding D did nothing - i.e. the Apple Hardware Test didn't start.

I'll run OS X recovery again. Perhaps there is something I didn't check...

...OK started up with command-R and ran the disk utility. The hard drive at the top level checked out when I ran Verify, Mactinosh HD checked out when I ran Verify, start up disk checked out when I ran verify.

Message was edited by: NickConnolly

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Answer 3

NickConnolly Author

Level 1

5 points

Oct 12, 2012 4:10 PM in response to John Galt

//If you cannot find anything wrong try starting the Mac in Safe Mode.//

I tried Safe Mode earlier. The grey progress bar appears and displays until it is about one-third of the way across. Then the progress bar disappears and the Mac goes back to Apple Logo and spinny thing. Doesn't ever get to the log on screen with "safe mode" in comforting red letters 🙂

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Answer 4

John Galt

Level 10

156,626 points

Oct 12, 2012 4:37 PM in response to NickConnolly

Thanks. Can't start in safe mode, and can't reinstall OS X... this is bad.

If I had to guess, there is a communication problem between your hard disk and the logic board. In any event I'm afraid this is a case for the Genius Bar.

😟

Make a reservation here:

http://concierge.apple.com/reservation/us/en/techsupport/

Don't despair, it could be something as simple as a cable.

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Answer 5

NickConnolly Author

Level 1

5 points

Oct 12, 2012 4:46 PM in response to John Galt

//Thanks. Can't start in safe mode, and can't reinstall OS X... this is bad.//

Yeah doesn't look good - but interesting that the recovery mode works.

Ran verify permissions on the disk and it lsited many issues with permissions - not sure how that would cause the problems I'm seeing but have run repair permissions anyway,😕

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Answer 6

Oct 13, 2012 5:23 AM in response to NickConnolly

- Reset PRAM:

turn on computer hold Command + Option + P + R keys simultaneously until you hear the startup chime for the second time.

- Reset SMC:

http://support.apple.com/kb/HT3964

After all that your computer still does not start? Try to reinstall mac os using internet recovery. Boot holding command + option + r until the globe logo appears.

If none of these procedures work, once again enter mac os utilities > disk utility > and check the first hard drive (above macintosh hd) the S.M.A.R.T status. If it shows as verified, ok. Otherwise it may be a hardware issue.

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Answer 7

NickConnolly Author

Level 1

5 points

Oct 13, 2012 7:38 PM in response to Guimesquita2

//

After all that your computer still does not start? Try to reinstall mac os using internet recovery. Boot holding command + option + r until the globe logo appears.

If none of these procedures work, once again enter mac os utilities > disk utility > and check the first hard drive (above macintosh hd) the S.M.A.R.T status. If it shows as verified, ok. Otherwise it may be a hardware issue.//

Been there - done that 🙂

Eventually rang up Apple and did the following:

Erased the hard drive

Reinstalled Mountain Lion

Restored the contents of the Mac from the Time Capsule. Hoorah! Computer worked 🙂...and then got slow and glitchy😐 then very slow 😕 then I shut it down 😟 then it wouldn't restart again (as before) 😢

Tried reinstalling Mounatin Lion without erasing hard drive this morning. Restarted after 50 minutes log in screen appeared but after logging in...nothing but a grey screen.

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Answer 8

NickConnolly Author

Level 1

5 points

Oct 19, 2012 12:30 PM in response to NickConnolly

The saga continues...

Booted into recovery mode. Erased hard drive (again). Re-installed OS (again) but haven't restored from backups.

Result? A jolly Mac that works happily (although somewhat lacking in Apps and files).

Conclusion: not a hardware issue.

New issue: I obviously want to restore all my stuff but at something in there is toxic.

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