Accidentally deleted Mac OS partition. Computer no longer boots into mac OS

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Accidentally deleted Mac OS partition. Computer no longer boots into mac OS

Alright so I have bootcamp and Window 10 works fine still. I was trying to make another partition from my much larger Mac OS partition while in disk utility in recovery mode and accidentally clicked "erase volume group" or something to that affect. The process took seconds and my entire hard drive other than bootcamp was unallocated space. Inside of Disk Management in windows, I can still see the space. It says Healthy (Primary partition).

I need to do this while saving the data. I have a USB drive but can someone tell me how to either remake the partition that my Mac OS and important files are on or secondly how to read and save my files either from Windows or from another Mac I can connect to this one using a USB C cable while the files are not in a mounted proper partition??

Thanks!

MacBook Pro 15″, macOS 10.15

Posted on Jan 3, 2023 09:15 PM

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Answer 1

almix12 Author

Level 1

5 points

Jan 3, 2023 11:20 PM in response to MrHoffman

Thanks for the quick reply. Is it really all gone if I don't have backups?? I used to backup stuff on external hard drives but they themselves kept breaking and I kept losing many TBs of files and backups so stopped bothering.

I feel like it was wayy too easy to just click the wrong button and enter my iCloud password (it asked me for it to turn off "find my mac") for everything to just be gone instantly like that. It took a matter of seconds leading me to believe it's still there and that I could do something in the data recovery realm to save it. It just thinks it's erased, it hasn't been written over. Any idea how I can save it before I erase the whole storage volume?

Thanks,

Alex

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Answer 2

Jan 4, 2023 10:42 AM in response to almix12

Clobbering a partition clobbers the data.

Clobbering a partition group clobbers the whole group.

Clobbering data with no backups does not end well.

Clobbering data on an SSD and with no backups means no data recovery.

SSDs work very differently from hard disks, and “scavenging” for recovery is not an option; freed sectors are erased.

The Mac itself can be reloaded, but anything in the clobbered partitions is gone.

And whether the Windows partition can be recovered without starting over is unclear, but you might want to back that up while you can still get at it. And I’d start over.

Partitioning and re-partitioning should be approached with great caution. Partitioning goes wrong more often than any of us might prefer, particularly with mixed operating systems.

Operating without backups means you’re one crash or corruption or dunk or theft or loss or hardware failure or errant command away from data loss. About the only way to mark data as valuable is with backups. If the data is sufficiently valuable, with some combination of multiple and rotating and off-site backups.

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