iMac freezes on startup

[rhatswell]

Hi, I'm a new member here. I'm looking to get some advice if it all possible.

I have been given an iMac A1200 (2006) which I'm looking to revive. I don't know the history but I can tell it has been opened up before. The problem is that it freezes on startup. When I power it on the apple logo appears and then the spinning wheel appears which goes round and round for about 30 seconds or so then it just stops and that's as far as it gets. I'm trying to figure out the problem. I know it may involve a little bit of trial and error. The hard drive has been changed so I know it's not that so any advice would be appreciated before I look into spending any money.

 

[Cory Cooper]

Hello and welcome.

-Your iMac is the iMac (24-inch) model from 2006, correct?
-Do you know who performed the hard drive replacement?
-Did you get the install discs that came with the iMac?
-Do you know what version of OS X is installed?

C

 

[honestone]

Besides the pertinent questions asked by Cory, how are you making posts here? Also, do you have access to another Mac? I wonder if you need some disk cleanup/maintenance/repairs, along with other things. Except for some disk cleanup and maintenance tasks, you'll need to "be on the iMac" via an external method in order to do such tasks completely, and especially for repairs. Once we know what Mac OS you are using, we can better assist you.

 

[rhatswell]

Thanks for the replies.

Answers to your questions are as follows...

-Your iMac is the iMac (24-inch) model from 2006, correct? Yes

-Do you know who performed the hard drive replacement? The iMac was given to me. I do not know the history. All I was told was the hard drive had been changed. The iMac had been used since the hard drive was replaced.

-Did you get the install discs that came with the iMac? No install discs came with it.

-Do you know what version of OS X is installed? I'm not sure, it was either Leopard or Snow Leopard. I haven't been able to get far enough to see. It loaded up to the login screen once. Since then, it freezes on startup.

I do have a access to a MacBook Pro as well that's running El Capitan so I should be able to access the iMac via an external method.

 

[honestone]

OK, that's good information. We need to know the specific MacBook Pro model you have. It should have either one Firewire 800 port, or one Thunderbolt port on it. Once we know the model, we can then advise you on how you can use the MacBook Pro to access the iMac and perform some diagnostics/repairs on it.

 

[rhatswell]

The MacBook Pro is A1297, 17-inch, Mid 2009. It does have a Firewire port on it.

 

[honestone]

OK, both of your Macs have a Firewire 800 port. What you'll need to do is first purchase a Firewire 800 cable. Next, with both machines off, use the Firewire 800 cable and plug into the Firewire 800 ports on each machine.

After that, boot the MacBook Pro. When it completes booting up, power on the iMac, and hold down the T key on its keyboard. What you are doing is booting your iMac in Target Disk Mode. Assuming that works, you'll see an icon of the iMac's internal drive on the MacBook Pro's desktop. From there, you can use whatever tools you have to look at, clean up, and repair that hard drive.

 

[rhatswell]

OK, thank you for the info. I will get a cable and give that a go and see how I get on.

 

[honestone]

OK, thank you for the info. I will get a cable and give that a go and see how I get on.

OK, we'll be here to help you. Just to help you out some more, here are a couple of links that discuss Target Disk Mode:

https://support.apple.com/kb/PH10725?locale=en_US (even though Mountain Lion is in the title, it still applies to any Mac OS)

http://osxdaily.com/2010/04/07/how-to-boot-a-mac-in-target-disk-mode/ (you have a Firewire 800 port on each of your Macs)

 

[rhatswell]

Hello again. I have now got a firewire cable and I have booted the iMac in Target Disk Mode and can now see it on the MacBook Pro. Can I ask what tools I could use to check and cleanup the hard drive?

 

[honestone]

Hello again. I have now got a firewire cable and I have booted the iMac in Target Disk Mode and can now see it on the MacBook Pro. Can I ask what tools I could use to check and cleanup the hard drive?

I suspect you do not have a third party maintenance program like TechTool Pro or Disk Warrior, so the only one you can use right now is Disk Utility, which is located in the Utilities Folder, which is within the Applications folder (on the MacBook Pro).

Disk Utility should be able to Verify and Repair the drive (I believe the actual title of those functions is "First Aid"), both at the Volume (ie, top) and Partition (ie, secondary) levels. But, if you could answer one other question, what OS are you using on the MacBook Pro? The reason I ask is that if it is not El Capitan (OS 10.11.x), then the version of Disk Utility you will be running also can perform the function "Repair Permissions" on the iMac's drive. You would do that after running the Verify and Repair functions.

Disk Utility will not perform many cleaning functions. Once you get the iMac running again (ie, can boot from it), we can then talk about an excellent, free, and solid program called Onyx that can perform some useful cleanup tasks. Plus, you can do some cleaning on your own.

 

[rhatswell]

Hello again. To answer your question, the MacBook Pro is running El Capitan 10.11.3. I have ran First Aid on the iMac's hard drive. I have uploaded 2 screenshots of the results of the First Aid test. One of the screenshots mentions problems were found with the partition map. Can you please advise on how to deal with that?

 

[honestone]

OK, you can check continue for each one and then you should be offered the opportunity to perform repairs. The only risk is that assuming yiu have not backed up the iMac's drive, you might need to Erase, Format, and if necessary, partition that drive. You would then lose everything on that drive, and hence you would need to start from the beginning and install the OS you want, and any third party applications you have. All of that assumes, of course, that the drive is fine. From the screen shot of "HD", that seems to be the case.

 

[rhatswell]

OK, well as this iMac was given to me and I was told that there was nothing on there that needed saving, I have no issue with erasing and formatting the drive and starting again. I can buy a version of OSX and go from there. Am I right in saying that this will run OSX 10.7.5 and no later?

 

[honestone]

Yes, the latest Mac OS that iMac can run is OS 10.7.5. But, I do not believe you can purchase that. You would need to purchase the last version of Snow Leopard, OS 10.6.8, and then upgrade, through the App Store, to OS 10.7.5 (for free). Here is the link about OS 10.68.:

http://www.apple.com/shop/product/MC573Z/A/mac-os-x-106-snow-leopard

I'm not exactly sure if that will give you the latest version of OS 10.6.8, but after you install it, you can download and apply the latest OS 10.6.8 Combo Updater from here:

https://support.apple.com/kb/DL1400?viewlocale=en_US&locale=en_US

But, try and first let Disk Utility repair the drive/partition, and let us know the results.

 

[rhatswell]

OK, now both processes seem to be OK but the iMac still freezes on startup. Is there anything else I can try or shall I move on to looking into wiping the drive and starting again?

 

[honestone]

Darn! Sorry that did not help. From the screen shots, it appears the drive is OK. Too bad you don't have Disk Warrior, as that venerable (but somewhat expensive) program can do more than Disk Utility.

Maybe someone else on here has some other ideas, but one would think that would have cured the issue. I guess the next step would be to download Snow Leopard to your MacBook Pro, reboot again in Target Disk Mode, use Disk Utility to Erase, Format, and if necessary, partition the iMac's drive, then install Snow Leopard on it, and then re-boot the iMac. Just hope that works.

 

[rhatswell]

OK, many thanks for all your help honestone - really appreciated. I did further investigation yesterday and spent several hours playing with this iMac and now I'm at a complete loss. List of things I did last night are as follows..

• Wiped the existing hard drive and tried to boot off a install disc. It was Leopard but froze on startup.
• If I power up the iMac and boot off nothing I get a flashing folder with a question mark which I expect as there is nothing on the drive.
• If I hold down the Option Key, the system can see a USB or Install Disc, I can select one and it will start to load but freeze.
• Put a different hard drive in - no change.
• Swapped out the memory - no change.
• Reset the PRAM - no change.
• Tried to boot into Safe Mode. Some text came up, I didn't really understand what it meant but have uploaded a screen shot.

What else could it be - logic board perhaps?

 

[honestone]

I am at a complete loss, given everything you tried. It also looks like you have the Install Leopard DVD. How did you try and boot the iMac from the DVD? The "standard" way would be to hold down the C key while the iMac starts up, and then the machine would try to boot directly from the DVD. If you already tried that, but it did not work, then I am perplexed!. Maybe someone else has some ideas.

 

[Cory Cooper]

If you are trying to startup from an install disc, is it a retail disc or a set of gray discs that shipped with another Mac? You can't use the gray discs from any Mac other than the ones that would have come with your 24", as they won't startup any other Macs and can cause a kernel panic like you are getting.

From one of your photos, it shows Darwin Kernel Version 8.0.5, which is Mac OS X 10.4.x Tiger, which may not be supported by your iMac depending on the version. It originally shipped with 10.4.7 or 10.4.8, so if you are using a version previous to that, it will not work.

If it is a retail OS X install disc, let us know what version and revision are printed on the label.

C