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Help needed shutdown and boot up problems

thewall

thewall

macrumors regular
Original poster
Oct 2, 2007
156
39
U.K
I'm trying to get my daughters 2014 27" iMac up and running after the internal hard drive failed (flashing question mark)
I thought instead of taking the screen off and installing a new drive i could run it of an external drive, so managed to install Os and all apps seem to work ok but the trouble I'm having is that it won't restart or shutdown i have to switch it off manually then the reboot take an age sometimes i have to hold down the option key and pick the drive to boot from, it only shows the new ssd.Is the mac looking for the failed drive first.
The old drive still shows in disk utility do i erase it completely.
I didn't think it was going to be this hard,'m under pressure as i made a promise!!!
Also i'm not a techy just following YT vids where everything goes right
 

Change your Mac startup disk

Change the startup disk of your Mac using Startup Disk settings.
support.apple.com support.apple.com

It sounds like you did not select a startup disk. When that happens, the system spends time searching around for available boot drives, and that takes time.

Set a startup disk following the instructions at the link above.
 
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If you still struggle with booting, after properly setting the Startup Disk, then you may simply be having problems with the old hard drive. It may be close to failure, and the only way to completely avoid problems would be to physically disconnect the drive. Erasing may or may not help, and the erase may simply fail, perhaps leaving the drive with an incomplete erase, maybe leaving you with a worse outcome. AND, "allowing / requiring" you to do your next task, which would again be physically unplugging the drive. and, THAT needs someone with more than a little experience with computer repairs. (Best would be to replace a failed/failing internal drive, but that would be your choice)
 
Hi Weasel Boy selected start up disk and still no change, when i click restart all the open windows vanish also the menu bar and it sits there for at least 5 mins with the desktop picture and the dock then the screen goes blank and a message says "the mac restarted because of a problem press any key" then i'm back on the login screen.
If i click shutdown the screen goes that dark blue and sits there for about 5 mins then restarts to the login screen.
this is a brand new ssd with a clean install i started with Yosemite to High Sierra to Big Sur once up and running everything is working fast and clean
 
DeltaMac said:
If you still struggle with booting, after properly setting the Startup Disk, then you may simply be having problems with the old hard drive. It may be close to failure, and the only way to completely avoid problems would be to physically disconnect the drive. Erasing may or may not help, and the erase may simply fail, perhaps leaving the drive with an incomplete erase, maybe leaving you with a worse outcome. AND, "allowing / requiring" you to do your next task, which would again be physically unplugging the drive. and, THAT needs someone with more than a little experience with computer repairs. (Best would be to replace a failed/failing internal drive, but that would be your choice)
Click to expand...
yes i would agree with all you are saying i tink she can live with it as it is
 
Have you tried an NVRAM reset? From OFF, press and release the power button, and immediately press and hold Option-Command-P-R.
You should get a boot chime. Keep holding the same 4 keys to get 2 more boot chimes, then, release those keys, holding only the Option key (to bring up the boot select screen. Click the icon for your boot drive, should continue to boot. When you are back at your desktop, first step is to go back into System Preferences/Startup Disk, and re-select that same boot drive (the reset will delete that setting).
Now, shut down that iMac. wait for that, if you still need to. Give it 10 or 15 minutes. (If it still does not shut off - screen goes black - even after 20 minutes, then something else is happening - could be that old hard drive just doesn't want to "help" with booting and shutdown.)
If you are OK with that, just be aware that the old hard drive COULD completely fail, giving other annoying issues, such as completely shutting off the next time you try to reboot. It's common during boot, that a failed internal drive can fail the power on test, resulting in a complete power off, even though you are trying to boot (something to consider, anyway)
 
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Get booted up from the external SSD.

Open disk utility.
IMPORTANT: go to the "view" menu and choose "show all devices"
Can you "see" the presence of the internal (problem) drive in du?
You may see more than one line for it (top line represents the physical drive, lines below represent logical volumes on the physical drive).

If you can see the physical drive (with logical volumes below), I'd try this:
Click on the physical drive to select it, then try "first aid".
What kind of report do you get?
Then I'd repeat this process for the NEXT line down, and so forth.

Disk utility might be able to correct problems with the drive and get it mounted on the desktop.

IF you can get this far, and IF you are able to access the files on the drive, now would be a good time to copy anything you want to keep OFF OF the internal drive, to some other location.

Afterwards you can open disk utility again and this time try erasing the entire drive (once more, click on the line on the left that represents the physical drive). Erase to "APFS, GUID partition format".

If you're able to erase the internal drive, you might just let it sit there "in place, empty, but otherwise not used" -- assuming you can now boot and run from the external SSD without problems.

IF you cannot get the startup disk pref pane to work as it should
BUT...
IF you can still get booted (from "off") by using the "option key trick"
THEN...
Just "do what you have to do".
 
DeltaMac said:
Have you tried an NVRAM reset? From OFF, press and release the power button, and immediately press and hold Option-Command-P-R.
Click to expand...
Hi DeltaMac did a NVRAM reset, now the restart and shutdown work as they should albeit a little slow so will see what happens, now i have put it to sleep but after about 5 mins it starts loading again to the login screen on a loop
 
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does some of the problem lie with the fact that i'm trying to start up and shut down with a HD connected to a usb, i would assume this would be slower as usb ports are not as fast as the internal connections, would this help if i disconnected the external HD and started the mac in os recovery and select DU and erase the internal HD
 
thewall wrote:
"Tried first aid and it could not repair drive"

Can you get back in to disk utility, and try to ERASE the internal drive instead?
Or... is there no access permitted to it at all...?
 
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