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Richard, Mac Genius
Category: Mac
Satisfied Customers: 43266
Experience:  Apple Computers Specialist
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- I have a serious problem with my iMac. The startup

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Hello - I have a serious problem with my iMac. The startup spinning wheel stops after about 30 seconds and the system will not go any further. I have tried all the usual 'fixes' using cmd-r, cmd-s and fsck -fy. It reports that the hard drive is OK but reboot brings back the same problem
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To be sure, it is not getting to the desktop at all correct?
It just freezes on startup?
Customer: replied 3 years ago.

That is correct

thank you
Power off the Mac, then hold down SHIFT and power on the mac and keep Shift held down until it either reaches the desktop or it stalls.
Let me know which happens please.
Customer: replied 3 years ago.

Already done all these - it stalls

I cannot access email while the computer is not working

ok, I only see cmd-r, cmd-s and fsck -fy can you tell me everything else you have tried please.
Customer: replied 3 years ago.

sure - sorry I didn't give everything. I started out with shift on startup - then went to option on startup, then cmd-option-p-r on startup, cmd-r on startup, finally cmd-s on startup and ran fsck -fy and fsck_hfs -f /dev/disk0s2

ok, disconnect everything apart from the power on the iMac and then try to start it.
What then happens?
Customer: replied 3 years ago.

Everything disconnected - took power lead out as well. Replaced power lead only and same thing

It is then likely the Sata port on the motherboard has failed.
To confirm this we need to do a reinstall, but this removes all data, so before we do this, is there any data you need to backup first?
Customer: replied 3 years ago.

Yes - but my last backup was 10 days ago, so not a serious problem

Can you do the following please
Start the computer and hold down the Command (⌘) and R keys while the computer starts.
Select “Disk Utility,” and then click Continue.
Select your startup disk from the list on the left, and then click the Erase tab.
From the Format pop-up menu, select Mac OS Extended (Journaled), type a name for your disk, and then click Erase.
After the disk has been erased, choose Disk Utility > Quit Disk Utility.
Select Reinstall Mac OS X, click Continue, and then follow the instructions.
Let this complete and when it has, tell me if the Mac now starts please
Customer: replied 3 years ago.

Before doing this, is it not possible to get a working OS onto an external drive?

You mean run OSX from an external drive to power the computer?
Customer: replied 3 years ago.


No sorry, it can only run from the primary internal hard disk
Customer: replied 3 years ago.

OK - but all my very expensive application software is also on the internal disk. Would there be any chance of recovering anything at all after the re-format

No sorry, the only recovery you can do is to take it into a store and have them physically remove the hard disk from the computer.
They then connect it as a slave to another computer and your personal files can be copied off it.
Programs you will have to reinstall again.
Customer: replied 3 years ago.

Thanks Richard - I'm not happy about doing the erase. The computer is still under warranty (purchased in July last year), so I think I will go down the warranty route to get a fix

I can understand, which is why I asked if you had data you needed to keep. They can then replace the motherboard to see if thats the issue, else its the hard disk and thats going to require and erase.
If you would like any additional information or assistance, please do not hesitate to let me know.
And if you can take a second to rate my service, that would be greatly appreciated.
Thank you
Richard and 4 other Mac Specialists are ready to help you
Customer: replied 3 years ago.

Using Disk Utility, I have transferred all files from my startup drive to an external drive. I am now trying to restore the system from a time machine backup. I'll let you know how I get on