I am trying to reinstall OS X using Disk Utility, but I keep running into problems. I always get errors like ‘unable to write to the last block of the device’ and ‘unable to delete the CoreStorage Logical volume Group’ whenever I try to erase/partition the HD. Anyone have any solutions?
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Issues with fixing Mac using Disk Utility
- Thread starter DUThrowaway
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Is the disk encrypted with FileVault by any chance? That second error message sounds vaguely familiar to me and I think I encountered it a year or so ago when trying to rebuild a FileVault'ed Macbook, and from memory the solution was to decrypt it prior to erase the disk.
Installing macOS via Internet Recovery Mode
- Select the ‘Apple’ logo and go to ‘System preferences> Network.’
- In the left-hand menu, select the network that you’re currently using.
- Click the ‘Advanced’ button.
- Find your network in the ‘Preferred networks’ list.
- The network’s security protocol should be listed next to it in the ‘Security’ column.
- Restart your Mac while holding down the ‘Option+Command+R’ keys.
- Release these keys as soon as you see the Apple logo.
- Once your Mac boots, the message ‘Starting Internet Recovery’ appears
- Select Reinstall macOS
I am 99% sure it isn’t, but I can’t really check as I can only go on my Mac in Recovery Mode.
Unfortunately, I can only enter recovery mode, so that solution won’t work for me.
MacBook Air (13-inch, Early 2015), IIRC the OS was 10.12.
For the remedy, follow the steps at the link below. That should get you going. I ran into the same thing several years ago.
Unable to delete the core storage local volume group
Currently, I'm trying to delete one of my partitions but for some reason it's giving me this issue: Does anyone know how I could go about clearing this?
I still get 'unable to delete the CoreStorage Logical volume Group' with that method in Terminal.For the remedy, follow the steps at the link below. That should get you going. I ran into the same thing several years ago.
Unable to delete the core storage local volume group
Currently, I'm trying to delete one of my partitions but for some reason it's giving me this issue: Does anyone know how I could go about clearing this?apple.stackexchange.com
"I have a backup and am okay with erasing the SSD."
Have you tried booting to internet recovery?
And THEN erasing the drive completely and re-installing the OS?
There are TWO approaches to this. READ EACH CAREFULLY.
First approach:
Command-OPTION-R
at boot.
This will install the most recent version of the OS that will run on the MBair.
However, you may not want this (that is, you might want an older OS like Sierra).
Second approach:
Command-OPTION-SHIFT-R
at boot.
This will install the earliest version of the Mac OS that shipped with the MBair.
For a 2015, that might be OS 10.11 El Capitan.
From that point, you could then take steps to get back to Sierra.
See this URL:
YOU have to decide what you want to do.
In my opinion, if you have a Mac, and it's not working, then any OS that GETS IT WORKING AGAIN is a good place to go. From that point you can pursue other options.
A third approach, but it will cost you about $20:
There are sellers on ebay who will sell you a USB flashdrive with the OS installer of your choice pre-installed on it and "ready to boot".
You then boot from the flashdrive and run the installer to install onto the internal drive. But again, these aren't free.
ONCE YOU GET BOOTED:
Open disk utility.
Check to see if there is a "view" menu. If there IS, choose "show all devices" (VERY IMPORTANT STEP)
Now, select the PHYSICAL internal drive (top line "on the left").
Erase it (what you erase TO depends on which OS you're installing). If it's High Sierra or earlier, choose "Mac OS extended with journaling enabled, GUID Partition format".
Once the drive is erased, open the OS installer and start "clicking through".
Have you tried booting to internet recovery?
And THEN erasing the drive completely and re-installing the OS?
There are TWO approaches to this. READ EACH CAREFULLY.
First approach:
Command-OPTION-R
at boot.
This will install the most recent version of the OS that will run on the MBair.
However, you may not want this (that is, you might want an older OS like Sierra).
Second approach:
Command-OPTION-SHIFT-R
at boot.
This will install the earliest version of the Mac OS that shipped with the MBair.
For a 2015, that might be OS 10.11 El Capitan.
From that point, you could then take steps to get back to Sierra.
See this URL:
Reinstalling macOS? Here's How to Choose the Version You Want
In the process of reinstalling macOS? Discover the step-by-step guide on how to choose the version you want, ensuring a smooth transition.
www.macobserver.com
YOU have to decide what you want to do.
In my opinion, if you have a Mac, and it's not working, then any OS that GETS IT WORKING AGAIN is a good place to go. From that point you can pursue other options.
A third approach, but it will cost you about $20:
There are sellers on ebay who will sell you a USB flashdrive with the OS installer of your choice pre-installed on it and "ready to boot".
You then boot from the flashdrive and run the installer to install onto the internal drive. But again, these aren't free.
ONCE YOU GET BOOTED:
Open disk utility.
Check to see if there is a "view" menu. If there IS, choose "show all devices" (VERY IMPORTANT STEP)
Now, select the PHYSICAL internal drive (top line "on the left").
Erase it (what you erase TO depends on which OS you're installing). If it's High Sierra or earlier, choose "Mac OS extended with journaling enabled, GUID Partition format".
Once the drive is erased, open the OS installer and start "clicking through".
Still getting the same issue with being unable to delete the logical volume group. Mac might be unsalvageable."I have a backup and am okay with erasing the SSD."
Have you tried booting to internet recovery?
And THEN erasing the drive completely and re-installing the OS?
There are TWO approaches to this. READ EACH CAREFULLY.
First approach:
Command-OPTION-R
at boot.
This will install the most recent version of the OS that will run on the MBair.
However, you may not want this (that is, you might want an older OS like Sierra).
Second approach:
Command-OPTION-SHIFT-R
at boot.
This will install the earliest version of the Mac OS that shipped with the MBair.
For a 2015, that might be OS 10.11 El Capitan.
From that point, you could then take steps to get back to Sierra.
See this URL:
Reinstalling macOS? Here's How to Choose the Version You Want
In the process of reinstalling macOS? Discover the step-by-step guide on how to choose the version you want, ensuring a smooth transition.www.macobserver.com
YOU have to decide what you want to do.
In my opinion, if you have a Mac, and it's not working, then any OS that GETS IT WORKING AGAIN is a good place to go. From that point you can pursue other options.
A third approach, but it will cost you about $20:
There are sellers on ebay who will sell you a USB flashdrive with the OS installer of your choice pre-installed on it and "ready to boot".
You then boot from the flashdrive and run the installer to install onto the internal drive. But again, these aren't free.
ONCE YOU GET BOOTED:
Open disk utility.
Check to see if there is a "view" menu. If there IS, choose "show all devices" (VERY IMPORTANT STEP)
Now, select the PHYSICAL internal drive (top line "on the left").
Erase it (what you erase TO depends on which OS you're installing). If it's High Sierra or earlier, choose "Mac OS extended with journaling enabled, GUID Partition format".
Once the drive is erased, open the OS installer and start "clicking through".