Accidently deleted Bootcamp from DU and now can't start Mac OS

If you have saved your files, one option is to re-install macOS, without erasing Macintosh HD. This will preserve any of your non-OS files.

Install macOS on an external disk and boot from it. Once booted from the external disk, you internal disk can be repaired.

See How to reinstall macOS from macOS Recovery - Apple Support for reference.

thwaitesy wrote:

Last login: Mon Nov  2 18:56:58 on console

cams-MacBook-Pro:~ cam$ diskutil list

/dev/disk0 (internal, physical):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:      GUID_partition_scheme                        *500.3 GB   disk0

   1:                        EFI EFI                     209.7 MB   disk0s1

   2:          Apple_CoreStorage Macintosh HD            404.4 GB   disk0s2

   3:                  Apple_HFS                         650.0 MB   disk0s3

   4:                  Apple_HFS BOOTCAMP                94.9 GB    disk0s4

Your BC partition was erased (not removed). Run

diskutil repairDisk disk0

and post the output. We may need to run fsck_hfs, if necessary.

Can you download and install GPT Fdisk (https://sourceforge.net/projects/gptfdisk/)? Your Recovery HD (disk0s3) is also not a valid file system.

/dev/disk1 (internal, virtual):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                  Apple_HFS Macintosh HD           +404.0 GB   disk1

                                 Logical Volume on disk0s2

                                 A273065A-5AA5-43F5-B5E6-EF8D43F51789

                                 Unencrypted

This the CS-contained HFS file system.

/dev/disk2 (external, physical):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:      GUID_partition_scheme                        *2.0 TB     disk2

   1:                        EFI EFI                     209.7 MB   disk2s1

   2:                  Apple_HFS UNTITLED                2.0 TB     disk2s2

   3:                 Apple_Boot Recovery HD             650.0 MB   disk2s3

This seems to be your external disk. You should also be able to see the HFS+ volume on the internal disk with your files.

Can you boot from the external disk and post the output of

diskutil list

We have not yet corrected the partition table. 😉

Can you install GPT Fdisk, and then we can correct the Recovery HD?

Also, post the output of

diskutil list

Can you post the output of

diskutil list

before we go to next step.

Step 1. We need to correct disk0s3. It is your Recovery HD. BCA recreated a second copy, since it did not find one.

Run (do not enter text like this).

sudo gdisk /dev/disk0

p (print current GPT)

t (Change partition type)

3 (GPT3)

AB00 (Apple Boot aka Recovery HD)

p (print GPT)

w (write updated GPT)

y (confirm, if needed)

Run

diskutil repairDisk disk0

and post the output of the session.

To be able to download files, your internal macOS partition must be mountable. Booting from an external macOS storage device will allow us to do that. If you current have Mavericks (10.9), I do not recommend using it on a Sierra (10.12) partition/disk.

If you can find a larger USB3 disk, we can install/upgrade to match the internal disk and then see what can be done.

You may also want to consider booting into Single-User Mode (Command+S as noted in Mac startup key combinations - Apple Support) and we can try to repair macOS, without an external boot.

Access is related to the user ids used. Leave your external disk connected, reboot and hold Alt/Option. Do you see the internal (Dark Grey) disk with macOS in the selection? If yes, does it boot properly, if you select it?

You internal disk is not shown in this. Let us try to repair the internal disk. Run

sudo fsck_hfs -f -y /dev/rdisk1

If you get an error that device is mounted, run Disk Utility and unmount disk1 (Macintosh HD) on the internal disk and retry.

This is not correct. In the steps you executed via GDisk, you have

partition table automatically reloaded!
Unable to open device '/dev/disk0' for writing! Errno is 1! Aborting write!

No changes were made. We need to temporarily disable SIP using csrutil in Local Recovery and then re-run the same steps.

External hard drive.

• Your macOS partition should not be manipulated by BC Assistant.
• Your Windows partition should not be manipulated by Disk Utility.

The following statement

thwaitesy wrote:

So I made a really dumb mistake and deleted my mac partition in DU instead of going through Bootcamp Assistant.

is very confusing.