iMac won't boot

[urchin]

Hi all,

I have read the forums for a while now, without feeling the need to register until today. Earlier on, I booted up my 2012 iMac (April) to do some work. It popped up about an update, and said I needed to restart which I did. I came back 15 minutes later to see that it was in sleep. After waking the mac, it showed a blank white screen, although I was still able to move the cursor. After waiting a while and seeing no change, I held down the power button to shut down. I then restarted the Mac, which then showed the Apple logo and the spinning wheel before restarting and showing once again, the Apple logo and spinning wheel. It was stuck on this screen whilst I was at dinner. When I returned, it showed setup assistant asking me to log into my Apple ID to set up iCloud. This then crashed and gave a message saying that it crashed and did I want to reopen it. I chose reopen and it left me with a white screen.

I left it for a while before holding the power button down. It now just gets to the Apple logo and the spinning wheel, and doesn't do anything. I am unable to boot into safe mode. I have booted into disk utility and verified the disk which showed no problems, and I repaired permissions as well, with no luck.

Does anybody have any advice of what action to take next. I want to avoid reinstalling the OS at all costs due to the fact that I have foolishly never backed up the Mac. I attempted to backup the disk image in Disk Utility, but got error 61. Does anybody know what this is? I presume this is due to the fact that the external drive has NTFS file format, which I am in the process of backing up to a PC and changing the file format.

I hope somebody is able to help.

Thanks.

 

[SaSaSushi]

Have you tried SMC and/or PRAM reset?

SMC Reset

1. Shut down the computer.
2. Unplug the computer's power cord and disconnect all attached devices.
3. Wait fifteen seconds.
4. Attach the computer's power cord.
5. Wait five seconds, then press the power button to turn on the computer.

Reset PRAM

1. Shut down the computer.
2. Locate the following keys on the keyboard: Command, Option, P and R.
   You will need to hold these keys down simultaneously in step 4.
3. Turn on the computer.
4. Press and hold the Command-Option-P-R keys. You must press this key combination before the gray screen appears.
5. Hold the keys down until the computer restarts and you hear the startup sound for the second time.
6. Release the keys.

 

[urchin]

Have you tried SMC and/or PRAM reset?

SMC Reset

1. Shut down the computer.
2. Unplug the computer's power cord and disconnect all attached devices.
3. Wait fifteen seconds.
4. Attach the computer's power cord.
5. Wait five seconds, then press the power button to turn on the computer.

Reset PRAM

1. Shut down the computer.
2. Locate the following keys on the keyboard: Command, Option, P and R.
   You will need to hold these keys down simultaneously in step 4.
3. Turn on the computer.
4. Press and hold the Command-Option-P-R keys. You must press this key combination before the gray screen appears.
5. Hold the keys down until the computer restarts and you hear the startup sound for the second time.
6. Release the keys.

I have, yes. Still no luck.

I did read online that I am able to use the Recovery menu by holding Command-R, and click reinstall OS X, without loosing any of my data. Is this definitely the case, as I don't have a backup of my data?

 

[SaSaSushi]

I did read online that I am able to use the Recovery menu by holding Command-R, and click reinstall OS X, without loosing any of my data. Is this definitely the case, as I don't have a backup of my data?

Yes, it should simply replace the contents of your system with a default installation. Once installed again, all your files, your user information, account settings, installed programs, etc. will still be there.

 

[urchin]

Yes, it should simply replace the contents of your system with a default installation. Once installed again, all your files, your user information, account settings, installed programs, etc. will still be there.

Thanks. Will try it when I get in. Any idea as to why this happened? I would presume it's not the Fusion Drive failing as disk utility shows no problems?

 

[urchin]

Bump

 

[SaSaSushi]

Thanks. Will try it when I get in. Any idea as to why this happened? I would presume it's not the Fusion Drive failing as disk utility shows no problems?

It is almost impossible to say what could be at the root of your problems. Some key system files may have been corrupted or you be dealing with a hardware issue after all.

Did you try the Internet recovery? That is the next logical step.

Bump

Bumping is against the forum rules here so you want to avoid it.

 

[urchin]

It is almost impossible to say what could be at the root of your problems. Some key system files may have been corrupted or you be dealing with a hardware issue after all.

Did you try the Internet recovery? That is the next logical step.



Bumping is against the forum rules here so you want to avoid it.

Ah okay, thanks. I didn't realise.

It's downloading the OS now using internet recovery. I wasn't able to create an image, so am just hoping that my files are intact. Unfortunately, when I started the download, it said it would take 11 hours or download. I'm at 3 hours now, so will report back once it's downloaded.

Thanks for your help.

 

[SaSaSushi]

Ah okay, thanks. I didn't realise.

No worries, and believe me I understand your frustration.

It's downloading the OS now using internet recovery. I wasn't able to create an image, so am just hoping that my files are intact. Unfortunately, when I started the download, it said it would take 11 hours or download. I'm at 3 hours now, so will report back once it's downloaded.

Yeah, I meant to mention that the biggest drawback of using Internet recovery is it can be an incredibly slow process because it must first download the necessary software.

Hopefully, that will do the trick for you and maybe it was just some system file that was corrupted somehow.

I know you mentioned it is a 2012 iMac. Do you happen to have AppleCare on it?

I really recommend you start backing up once you get things in order again. A recovery from a Time Machine backup or a clone is lightning quick compared to what you're dealing with now.

 

[urchin]

No worries, and believe me I understand your frustration.



Yeah, I meant to mention that the biggest drawback of using Internet recovery is it can be an incredibly slow process because it must first download the necessary software.

Hopefully, that will do the trick for you and maybe it was just some system file that was corrupted somehow.

I know you mentioned it is a 2012 iMac. Do you happen to have AppleCare on it?

I really recommend you start backing up once you get things in order again. A recovery from a Time Machine backup or a clone is lightning quick compared to what you're dealing with now.

I was a bit surprised to see 11 hours; I thought it only downloaded the OS. It's down to 1 hour now though, so not long left.

Yes, I purchased Apple Care a few months back. I needed to get a new external HDD, which I put off over time as didn't expect the Mac to go wrong (bad excuse). My other external HDD isn't supported by Mac's and won't reformat.

I'd be surprised if it was a hardware error, due to the way that the problem occurred. Hopefully a few files got corrupt during the update, and this solves it.

Fingers crossed!

 

[urchin]

It finished downloading, and went through its normal installation process. After nervously watching it finish, the Mac returned to its original working state. It even loaded the programmes that were originally open just before the update when it crashed.

Thank you for all your help and advice. Buying a new external HDD is definitely on the to-do list.

 

[SaSaSushi]

I'm really glad to hear that it all worked out.

Yeah, definitely get an external and start backing up. Time Machine works really well.

Another thing you may want to do is make a Mavericks Installer thumb drive using Diskmaker X. This will save you some downloading time if you ever need to reinstall the OS again.

 

[urchin]

I'm really glad to hear that it all worked out.

Yeah, definitely get an external and start backing up. Time Machine works really well.

Another thing you may want to do is make a Mavericks Installer thumb drive using Diskmaker X. This will save you some downloading time if you ever need to reinstall the OS again.

Will do. Thanks.

 

[Tulani]

I'm really glad to hear that it all worked out.

Yeah, definitely get an external and start backing up. Time Machine works really well.

Another thing you may want to do is make a Mavericks Installer thumb drive using Diskmaker X. This will save you some downloading time if you ever need to reinstall the OS again.

what steps shall I use after downloading the dmg file?

 

[SaSaSushi]

what steps shall I use after downloading the dmg file?

Are you referring to Diskmaker X? All you need to do is download Mavericks (or Mountain Lion) in the Mac App Store and the app should find it automatically when you run it.

Any other questions can probably be answered by their FAQ.

 

[Tulani]

I downloaded Mavericks when it launched and installed on my Mac. Do I need to do another download for this purpose? Thanks

 

[SaSaSushi]

I downloaded Mavericks when it launched and installed on my Mac. Do I need to do another download for this purpose? Thanks

If you downloaded Mavericks from the Apple Mac Store, the installer file will still be in your Applications folder unless you manually remove it.

Therefore, you won't need to download it again for the purposes of making a USB thumb drive with Diskmaker X. Moreover, once you're done creating the thumb drive installer, you can delete the Mavericks installer from your Mac if you like to reclaim drive space.

 

[Tulani]

If you downloaded Mavericks from the Apple Mac Store, the installer file will still be in your Applications folder unless you manually remove it.

Therefore, you won't need to download it again for the purposes of making a USB thumb drive with Diskmaker X. Moreover, once you're done creating the thumb drive installer, you can delete the Mavericks installer from your Mac if you like to reclaim drive space.

thank you

 

[Weaselboy]

I downloaded Mavericks when it launched and installed on my Mac. Do I need to do another download for this purpose? Thanks

Yes, you will need to redownload. If you ran the installer after downloading to install Mavericks, that installer file deleted itself at the end of the install and is gone.

 

[Tulani]

Yes, you will need to redownload. If you ran the installer after downloading to install Mavericks, that installer file deleted itself at the end of the install and is gone.

ahaa thanks for clearing that up

 

[SaSaSushi]

Yes, you will need to redownload. If you ran the installer after downloading to install Mavericks, that installer file deleted itself at the end of the install and is gone.

Strange, I haven't installed Mavericks in a while (this Mac came with it installed) but I know I still had the installer in my Applications folder when I created my Diskmaker X installer with my previous iMac.

I seem to recall it asking whether I wanted to delete the installer file after finishing installation on my old Mac, but if you say so I will chalk it up to my faulty, aging memory.

Edit: Indeed it was my faulty memory. It turns out that I restored the installer file from a backup when I made my thumb drive installer.

A tip for those who want to keep the installer on hand after installation is to simply move it out of the Applications folder before installing. If it is located anywhere else, it won't be automatically deleted by the installstion process.

 

[Fishrrman]

urchin wrote above:
[[ Buying a new external HDD is definitely on the to-do list. ]]

If you use either CarbonCopyCloner or SuperDuper to create a bootable clone of the internal drive, you will then have "an alternative boot source" for future "I can't boot!" experiences such as the one from which you've just recovered.

Example:
If you had had a bootable clone when your iMac wouldn't boot on it's own, all you probably would need to do is:
1. Connect backup cloned drive
2. Reboot via startup manager (hold down option key at startup until startup manager appears, then select external clone and hit return)
3. Mac should then boot from clone.

At that point, you should be looking at an exact copy of what your internal drive was (the last time you backed it up).
You could either then attempt to repair the internal drive, or, just "Re-clone" the contents of the backup BACK TO the internal drive.

Far, FAR easier than struggling with the recovery partition or "internet recovery", etc.

 

[urchin]

urchin wrote above:

[[ Buying a new external HDD is definitely on the to-do list. ]]



If you use either CarbonCopyCloner or SuperDuper to create a bootable clone of the internal drive, you will then have "an alternative boot source" for future "I can't boot!" experiences such as the one from which you've just recovered.



Example:

If you had had a bootable clone when your iMac wouldn't boot on it's own, all you probably would need to do is:

1. Connect backup cloned drive

2. Reboot via startup manager (hold down option key at startup until startup manager appears, then select external clone and hit return)

3. Mac should then boot from clone.



At that point, you should be looking at an exact copy of what your internal drive was (the last time you backed it up).

You could either then attempt to repair the internal drive, or, just "Re-clone" the contents of the backup BACK TO the internal drive.



Far, FAR easier than struggling with the recovery partition or "internet recovery", etc.

Ah I see. Thank you very much. Any particular drives to recommend. USB or FireWire? I was thinking about getting a WD My Passport for Mac (USB 3.0).

 

[SaSaSushi]

Ah I see. Thank you very much. Any particular drives to recommend. USB or FireWire? I was thinking about getting a WD My Passport for Mac (USB 3.0).

You should have no problems at all booting from any external drive over Firewire. The same cannot be said for USB, unfortunately. It is hit or miss with boot support on the USB controllers.

USB 3 is clearly a far better alternative in terms of speed though. My recommendation is USB but to just check to make sure the device you're purchasing has the ability to boot the OS prior to purchase.

 

[Fishrrman]

[[ Any particular drives to recommend. USB or FireWire? I was thinking about getting a WD My Passport for Mac (USB 3.0). ]]

Hmmm... I'd avoid WD drives, just heard too many bad reports about them.

Actually, if you know how to hold a screwdriver, I'd suggest something completely different.

You might get something like this:
http://www.amazon.com/dp/B003VKTJGW...UTF8&colid=R75PP4I2A0BE&coliid=I3DOKZ31SP7539

... and then shop for a 2.5" hard drive of your choice, and then put it together yourself.

ANYONE can do this.
The reason I suggest the "do it yourself" approach is that by bulding your own drive, you'll know what's in it. And if you ever have a problem you can take it apart because you know how it went together.

Then just initialize the drive using Disk Utility, and you're ready to go. You can create a cloned backup using CarbonCopyCloner or SuperDuper, or start a Time Machine backup if you wish.

Another possible course of action:
PARTITION the new drive. Use the first partition for a cloned backup, and let the second partition serve as your Time Machine backup. Then you can have the advantages of having both a backup clone AND "going back" with TM.

Final thought:
These days, USB3 is probably a better choice for drive connectibility than is firewire800. Faster and cheaper as well.

I boot and run my 2012 Mini via an SSD mounted in a plugable.com "lay-flat" USB3/SATA docking station. No problems after a year+ of HEAVY usage...