i am having a major issue with my macOS. I cannot restore or reinstall macOS. I get errors inside disk utility/first aid. I get a (circle with a line through it) when i start up. and when I do get the (apple logo) upon start up, it just stays there until i eventually power off and start over. I have tried everything except throwing it out the window. agh!!!
iMac 21.5″, macOS 10.15
Boot into your Recovery HD, restart you mac while pressing and holding down the Command and R keys.
After you have booted to your Recovery HD you should see a Utilities panel.
Select Disk Utility and press Continue.
Click View in the menubar and select Show All Devices.
What do you see on the left hand panel.
You should see the Disk probably called Apple SSD..........
Underneath that and indented you should see a Container Disk with a number.
Underneath the Container Disk and indented are the two Volumes usually called
Macintosh HD and Macintosh HD - Data, please see the screenshot below for reference.
Can you run Disk Utility First Aid on first of all the Disk,
then in turn the Container Disk and then the two Volumes.
What results do you get.
Have you been making regular backups of your mac to an external hard drive.
If Disk Utility First Aid does not give green ticks for the Disk and its Volumes then you
will have to erase and reformat the Disk. This will of course mean that you will lose
all of your data, that is why it is very important to make regular backups to an external HD.
After erasing and reformatting the Disk you would then quit Disk Utility and then select Reinstall OS
or Restore from Time Machine Backup if you had been making backups.
If you need to reinstall the OS from Apples Recovery Servers your mac should be connected to your router
directly via cable, WiFi is too unreliable. Do not use any other devices that share the same internet connection
whilst your mac is downloading.
To Erase and Reformat the Disk you highlight the Disk (AppleSSD.....) click on Erase.
From the following drop down give the Disk a name.
Format: APFS.
Scheme: GUID Partition Map.
Click Erase.
When Done quit Disk Utility.
Boot into your Recovery HD, restart you mac while pressing and holding down the Command and R keys.
After you have booted to your Recovery HD you should see a Utilities panel.
Select Disk Utility and press Continue.
Click View in the menubar and select Show All Devices.
What do you see on the left hand panel.
You should see the Disk probably called Apple SSD..........
Underneath that and indented you should see a Container Disk with a number.
Underneath the Container Disk and indented are the two Volumes usually called
Macintosh HD and Macintosh HD - Data, please see the screenshot below for reference.
Can you run Disk Utility First Aid on first of all the Disk,
then in turn the Container Disk and then the two Volumes.
What results do you get.
Have you been making regular backups of your mac to an external hard drive.
If Disk Utility First Aid does not give green ticks for the Disk and its Volumes then you
will have to erase and reformat the Disk. This will of course mean that you will lose
all of your data, that is why it is very important to make regular backups to an external HD.
After erasing and reformatting the Disk you would then quit Disk Utility and then select Reinstall OS
or Restore from Time Machine Backup if you had been making backups.
If you need to reinstall the OS from Apples Recovery Servers your mac should be connected to your router
directly via cable, WiFi is too unreliable. Do not use any other devices that share the same internet connection
whilst your mac is downloading.
To Erase and Reformat the Disk you highlight the Disk (AppleSSD.....) click on Erase.
From the following drop down give the Disk a name.
Format: APFS.
Scheme: GUID Partition Map.
Click Erase.
When Done quit Disk Utility.
You are Erasing the wrong thing, I have told you you need to Erase the Disk not the indented Volumes.
And if you were running macOS Catalina you should have the Disk then the Container Disk ,
then the Volumes Macintosh HD and Macintosh HD -Data.
Try again.
Highlight Apple HDD HTS541...
Click Erase.
Give the Disk a name.
Format: Mac OS Extended (Journaled) if reinstalling Sierra or APFS if you are reinstalling Catalina.
Scheme: GUID Partition Map.
Click on Erase.
When done quit Disk Utility.
Click on Reinstall OS press Continue.
What were the errors you got when using Disk Utility > First Aid.
rickyclark wrote:
I have been following instructions from a post above. So it’s been erasing for about 24hrs now.
See my earlier post -- your disk shows as "FAILING" which means it has ceased to function normally as a disk. A properly functioning disk would erase in about 20 seconds, at most. You need to replace it.
Okay so when you reboot to your Recovery HD using the Command and R key
and then ask it to reinstall the OS it will install the original OS your mac came preinstalled with from factory.
In your case it looks like macOS Sierra. macOS Sierra will only run on Mac OS Extended formatted disks, it cannot
be installed on APFS formatted Disks.
So go back to Disk Utility highlight the Disk and click Erase.
Give the Disk a name.
Format: Mac OS Extended (Journaled).
Scheme: GUID Partition Map.
Click Erase.
When Done quit Disk Utility.
Click on Reinstall OS.
If you want to have the mac reinstall the latest OS it can run then read this,
How to reinstall macOS – Apple Support
go to Other macOS Installation Options
As you have not provided what year your mac is it may be that it will install
macOS Big Sur.
Boot into the Recovery volume (boot with the Command + R keys held down), select Disk Utility and see if it can see your boot drive. If it can erase the drive and reinstall the System.
This will remove all your user data so be sure to have a full backup before attempting.
Should only take a few seconds to erase and reformat, as has been noted your HD is failing or has failed, you need to replace it.
You say you have tried everything, does that include a Safe Mode restart?
How to use safe mode on your Mac – Apple Support
If you have tried everything then could you list what that was so you do not get replies asking you to do stuff you have already tried.
As the iMac is notoriously difficult to get into it is probably prohibitively
expensive to get a Apple recommended service provider to replace the internal drive.
The easiest and cheapest option would be to buy an external drive.
See Old Toads post above.
Envoy Pro EX with USB-C or USB 3- best from a speed vs price standpoint - 1 TB $269
OWC Envoy Pro EX with Thunderbolt 3 - fastest if you have a Thunderbolt 3 port but more expensive - 1 TB $329
I Have tried safe mode, and I get the ( circle with the line thru it) so I power off and try (disk utility)
i have tried disk utility/ first aid and all I get is errors - in Macintosh hd and inside the container
I try to reinstall macOS and there is no disk place or disk for me to install it. (Blank with no selections) and it says there is a error
yes, I have tried this. And I would get “failed” on (Macintosh hd, Macintosh hdd) volumes. I would then click done.
i also tried to reinstall macOS with still no luck.
after doing all this, I restarted the Mac, and for some strange reason it’s no longer (Catalina). But now is trying to reinstall old operating system (Sierra). Even when I tried to reinstall that, I still got a error while trying to prepare installation.
There is a error when I try to erase Macintosh HD. Says “cannot be unmounted because it is in use by process 688 (kextcache)
couldn’t unmount disk : (-69888)
and my Mac is 21.5 ‘ iMac intel core i5 (late 2015)
and I never updated to Big Sur, I wish I did now when I got the update.
Ok gotcha, I was just doing it the way it said on the apple site. It said to do first aid on volumes 1st then work your way up.
but I have now been doing what you said. And erasing (apple Hdd) and it’s been about 2 1/2 hrs so far. Is it supposed to take that long? We shall see what happens. So far.....
but originally I was getting mounting errors,
freezes, or just not starting up completely.
rickyclark wrote:
How much does something like this might cost?
I just replaced an internal SSD on a MacBook Air, the 1 TB internal SSD was about $200 (from OWC) and it was $35 for a local shop to install it for me.
This is the error I get when trying to reinstall
Disk utility/first aid errors
