While I guess I’m not completely computer illiterate, as I get older it feels like I’m not far from it. Always before, when I’ve had problems I’ve been able to come here and, after some searching, find the answer to my problem. This time, maybe because I got frustrated, I didn’t think to come here until now. Here’s my situation… I have a 2019 27” iMac. I believe I was running the latest version of Monterey. I have Windows 10 in a Bootcamp partition that I run thru Parallels. For the last few weeks I’ve had a problem with the Mac side slowing down and getting the spinning beachball. I finally decided on Thursday to run Onyx. Onyx reported that “the Data volume needs to be repaired” and to startup in Recovery mode and repair it with Disk Utility. I did as it suggested, but when I ran First Aid on “Macintosh HD-Data” I got “File system verify or repair failed: (-69845)”. After rerunning First Aid several times and getting the same result I did some research on the net. I found a suggestion somewhere to run First Aid on what I guess would be the parent volume instead of the Data volume. That resulted in a green check and what I thought was a successful repair; however, when I restarted the computer it booted straight into Windows. When I restarted it while holding the “Option” key the only boot option that showed up is Windows. When I restart into recovery mode and pull up Disk Utility the Macintosh HD and Macintosh HD-Data is gone. The photo is of what shows up on the screen. Is there any way to fix what I’ve screwed up? Thanks.
![14F82131-C743-4C75-A221-3DCFBA2BE57B.jpeg]( "14F82131-C743-4C75-A221-3DCFBA2BE57B.jpeg")
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Boot issue
- Thread starter ChuckLDJ
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It’s a Fusion drive. Sorry I didn’t include that. I did try the reinstall in Recovery early this morning, but Macintosh HD doesn’t show up. The only thing that shows up is Bootcamp.
You will likely need to reset the fusion drive - https://support.apple.com/en-us/HT207584
This will reformat both drives (the fusion drive is two devices - a spinning hard drive, and a solid-state drive. Both are combined by software, so the system sees only one device, which is then partitioned as needed by the file system.
You may have one of the devices that is failing (judging by the error that you have been seeing when your tried the First Aid fix), and the fusion drive reset may fail because of that. If that is a result, then you may want to consider replacing both devices with only an SSD. And, that will result in noticeably better response from the system, as you will no longer be dragged down by the slower, mechanical hard drive.
(note that resetting the fusion drive erasing everything, including your Windows bootcamp installation)
This will reformat both drives (the fusion drive is two devices - a spinning hard drive, and a solid-state drive. Both are combined by software, so the system sees only one device, which is then partitioned as needed by the file system.
You may have one of the devices that is failing (judging by the error that you have been seeing when your tried the First Aid fix), and the fusion drive reset may fail because of that. If that is a result, then you may want to consider replacing both devices with only an SSD. And, that will result in noticeably better response from the system, as you will no longer be dragged down by the slower, mechanical hard drive.
(note that resetting the fusion drive erasing everything, including your Windows bootcamp installation)
I was hoping not to hear that. If I’ve got to deal with that I might pass this on to a family member and update to a 2020 27” with a SSD which brings up a question that is probably stupid. I have my time machine backups on an external HD. If I were to get a new (refurbished) machine could I use the time machine HD to get my old stuff on the new machine? Thanks.
Thanks. I thought I remembered reloading everything from my Time Machine HD when I got this current Mac, but as I’ve gotten older my memory isn’t what it used to be.
As I debate on what I’m going to do I’ll probably have some questions, which will most likely be stupid, since I’ve never dealt with an SSD. Any advice or input would be appreciated. Regardless, let me say that I sincerely thank you for taking the time to read through my mess and answer.
I've got to post this:
If you had a bootable cloned backup created with either CarbonCopyCloner or SuperDuper (instead of time machine), you'd be up-and-running now. (yes, I'm THAT confident in making that statement)
What happens if you boot to INTERNET recovery?
(this is NOT THE SAME as "the recovery partition")
Command-OPTION-R
at boot.
Try this, and get back to us.
Can you get booted to the internet utilities?
If so, open disk utility.
Go to the view menu and choose "show all devices".
Now, start at the top.
Do a "first aid" function ON EVERY ITEM you see in the list from the top down.
If you had a bootable cloned backup created with either CarbonCopyCloner or SuperDuper (instead of time machine), you'd be up-and-running now. (yes, I'm THAT confident in making that statement)
What happens if you boot to INTERNET recovery?
(this is NOT THE SAME as "the recovery partition")
Command-OPTION-R
at boot.
Try this, and get back to us.
Can you get booted to the internet utilities?
If so, open disk utility.
Go to the view menu and choose "show all devices".
Now, start at the top.
Do a "first aid" function ON EVERY ITEM you see in the list from the top down.
The photo in my original post is from “show all devices” after booting to internet recovery, but I’ll try to add it to this post. First Aid shows all the items okay. Except the ones grayed out.![BD6C9FA4-89E2-46C8-B555-DC2952A3B765.jpeg]( "BD6C9FA4-89E2-46C8-B555-DC2952A3B765.jpeg")
I've got to post this:
If you had a bootable cloned backup created with either CarbonCopyCloner or SuperDuper (instead of time machine), you'd be up-and-running now. (yes, I'm THAT confident in making that statement)
What happens if you boot to INTERNET recovery?
(this is NOT THE SAME as "the recovery partition")
Command-OPTION-R
at boot.
Try this, and get back to us.
Can you get booted to the internet utilities?
If so, open disk utility.
Go to the view menu and choose "show all devices".
Now, start at the top.
Do a "first aid" function ON EVERY ITEM you see in the list from the top down.
I tried resetting the Fusion drive today and it wouldn’t let me do it because of the Bootcamp partition. Here’s the screen cap.
"I tried resetting the Fusion drive today and it wouldn’t let me do it because of the Bootcamp partition."
Get rid of bootcamp.
Then... start over.
Get rid of bootcamp.
Then... start over.
Yeah. I kind of figured that, but how do I do that? I clicked on Bootcamp in Disk Utility and then “erase” and it asked me for a name and format.
I mentioned this before, but didn't see your answer.
What happens if you boot to INTERNET recovery?
(this is NOT THE SAME AS "the recovery partition")
Command-OPTION-R at boot.
If you connect to the net via wifi, you'll need your wifi password.
The internet utilities take a while to load, be patient "as the globe spins".
Can you get to the utilities screen using internet recovery?
What happens if you boot to INTERNET recovery?
(this is NOT THE SAME AS "the recovery partition")
Command-OPTION-R at boot.
If you connect to the net via wifi, you'll need your wifi password.
The internet utilities take a while to load, be patient "as the globe spins".
Can you get to the utilities screen using internet recovery?
Yes, you will need to change the format for the bootcamp partition, as it is NTFS. The idea here is that you have to remove that bootcamp partition, as you can't reset the fusion drive when there is a non-writeable partition in place.
One method to do that is to choose the device (line starts with "APPLE HDD ST20..." Erase that device, which will then remove all associated partitions (bootcamp, which is what you want to remove. Erasing the device takes that partition, too.) And, after erasing that drive, you will then be able to reset the fusion drive, following the steps that you tried to use before.
When I go to erase APPLE HDD… a dialog box comes up asking for a name and a format. What should I enter? I realize these questions probably sound stupid and/or ignorant but in 37 years of using computers this situation is a first for me.
Name and Format are your choice during an erase. You can name your Apple HDD anything you like. I have been erasing drives on Macs for nearly 30 years, and often choose names of Norse gods, or names of stars, or just the factory name that Apple continues to use - Macintosh HD or Macintosh SSD. Virtually any name you want to come up with is fine.
As for the format - Mac OS Extended (journaled) continues to be a useful choice. If you are installing a system newer than High Sierra, the drive will automatically be converted to APFS format, as a normal part of that system install.
As for the format - Mac OS Extended (journaled) continues to be a useful choice. If you are installing a system newer than High Sierra, the drive will automatically be converted to APFS format, as a normal part of that system install.
Unfortunately, I live out in the boondocks. The nearest Apple store is about an hour and a half away. I’ve still been tempted to make the drive, but I’m also dealing with some sort of stomach virus that’s been more aggravating than the computer problem.
Scheme is always going to be GUID partition map (unless you have some special need for a different scheme, such as preparing a drive for use with Windows, which would often be Master Boot Record. But, even if you intend to use Boot Camp for a Windows install, the Boot Camp Assistant will format the Windows partition for you. It's not necessary for you to choose that scheme when you are now trying to make the fusion drive - just use GUID at this point...)
This is what happens for me. I go to Disk Utility. I click “view all”. Then I click on “APPLE HDD ST2000…”. Then click “erase”. It asks for name so I just type in Mac. It asks for format so I have it at Mac OS Extended (Journaled). It asks for scheme so I have it at GUID Partition Map. Then click erase. When it’s finished, under “view all” it shows Mac beneath APPLE HDD ST2000…(see the attached photo). Apparently I’m still doing something incorrectly because when I go to Terminal and type “diskutil resetFusion” it tells me that I must have exactly one solid-state and one rotational disk drive.![D4BE1BDC-A444-4C56-A5D8-F8F074E24E5D.jpeg]( "D4BE1BDC-A444-4C56-A5D8-F8F074E24E5D.jpeg")
Scheme is always going to be GUID partition map (unless you have some special need for a different scheme, such as preparing a drive for use with Windows, which would often be Master Boot Record. But, even if you intend to use Boot Camp for a Windows install, the Boot Camp Assistant will format the Windows partition for you. It's not necessary for you to choose that scheme when you are now trying to make the fusion drive - just use GUID at this point...)
Well, now I feel more like an idiot than before I started. I could have sworn this machine came with Mojave installed but apparently it didn’t. The Fusion drive is now reset. Thanks for the help and sorry for the aggravation.