Can’t resize macOS partition (APFS error code 49187)

apfsdisk-utilityhard drivehigh sierrapartition

I'm unable to shrink my APFS macOS partition in Disk Utility or by using diskutil. When I try with either method, I receive error code 49187. There appears to be no reference for these codes and I can't find any information online. I have tried deleting Time Machine snapshots and that made no difference. First Aid on my disk reveals some kind of corruption in the partition map:

I tried what it said and First Aid only lets me scan my macOS partition in Recovery Mode. Using diskutil gives me Error starting file system repair for disk0: Invalid request (-69886).

Is there any way to fix this? I'm trying to add a FAT32 partition to my disk.

This is on macOS 10.13.3.

Best Answer

I solved this error for myself by the following steps, (to be sure I included all)

Time Machine snapshot delete fix
Decrypt harddrive from filevault

This resulted in the persistence of the error. But then I booted in recovery mode (reboot and hold cmd+R) and started the disk utility there. To my surprise the Disk Utility showed me different values for the free space of my partition. I only had 20g free instead of the 50g I tried to allocate each time.

When I did the normal partition steps in the recovery boot Disk Utility everything went fine and I am currently running Ubuntu 18.04.1 alongside Mojave 10.14.1 without problems, be it that I only have 20g.

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Can’t partition hard drive – “corrupt”, exit code 8

Your main volume has a minor error (orphaned blocks - invalid volume free block count) which usually can be fixed with diskutil repairVolume diskIdentifier entered in Terminal.app booted from another volume or disk.

Either boot to Recovery Mode (cmdR while booting) or Internet Recovery Mode (altcmdR while booting).
In the menubar > Utilities open Terminal
Enter diskutil list to get the disk identifier of your main volume.
- with CoreStorage disabled that's usually disk0s2
- with CoreStorage enabled that's usually disk2 or in the upper tenth (e.g. disk17). It's the one with the (internal, virtual) supplement.
  
  If it wasn't mounted enter diskutil cs list to get the Logical Volume UUID and try to mount it with diskutil cs unlockVolume UUID (replace UUID here with the UUID found previously). Repeat diskutil list to get the disk identifier.
Now check the volume with diskutil verifyVolume diskXsY (normal volume) or diskutil verifyVolume diskX (CoreStorage volume).
Then try to repair the volume with diskutil repairVolume diskXsY (normal volume) or diskutil repairVolume diskX (CoreStorage volume).

Cannot partition SSD in Bootcamp or Disk Utility

Many users have posted problems similar to yours. In every case, APFS in involved.

Below are the instructions for installing Windows 10.

Note: To get a better view of the images shown below, either click on an image or open an image in a new window.

(In your case, you can skip this step.) Remove all Windows related partitions that may have been created by previous attempts to install Windows. When finished, the output from the command diskutil list disk0 should appear similar to what is shown below. Other users should assume their sizes will be different.

/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_APFS Container disk1         500.1 GB   disk0s2

The command below will create the 150 GB "BOOTCAMP" partition on your internal drive. If you want a different size, then make the appropriate subsitutions. The space occupied by this partition will be used for installing Windows.

Note: The two sizes given in the command below need to equal the size of your disk0s2. In other words, 350.1 + 150 = 500.1.
```
sudo  diskutil  apfs  resizeContainer  disk0s2  350.1G  FAT32  BOOTCAMP  150G
```
Use the Disk Utility application to erase a 16 GB or larger USB flash drive. Enter the settings shown below in the popup window. When finished, do not remove the flash drive.
Use the Boot Camp Assistant to download the Window Support Software. Look for the "Action" pulldown on the Boot Camp Assistant menu bar. On my Mac, these files were downloaded to the ~/WindowsSupport directory.

Note: You can not download the Boot Camp Support Software for your Mac computer from any Apple website. You must use the Boot Camp Assistant to download an officially copy of this software.
Mount the Windows iso file and copy the contents to the "WINSTALL" volume. You will need the use the cp command from a Terminal application window. Below is the exact command I usually use. The string ESD-ISO is the name of the mounted ISO file from Microsoft. If necessary, make the appropriate modifications.
```
cp  -Rv  /volumes/ESD-ISO/  /volumes/WINSTALL
```
Note: This command will take a while to complete. Be patient!
Copy the Windows Support Software to the "WINSTALL" volume. Below is the exact command I usually use. If necessary, make the appropriate modifications.
```
cp  -Rv  ~/WindowsSupport/  /volumes/WINSTALL
```
Continue starting at step 3 of my answer to the question Boot Camp Assistance is stuck on create a partition?

Best Answer

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Can’t partition hard drive – “corrupt”, exit code 8

Cannot partition SSD in Bootcamp or Disk Utility

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