Unable to mount external HDD

[vmvmvm]

Hi Everyone, I have a relatively new external HDD that was ejected in some wrong way (possibly when was backuping time machine, or something similar) on a Catalina system.
Now it's not visible, the volume is Grayed out in Disk Utility and can not mount it back, not on the initial computer, not on other macbook.

"diskutil list" in terminal shows

/dev/disk0 (internal, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *1.0 TB disk0
1: EFI EFI 209.7 MB disk0s1
2: Apple_CoreStorage HD 999.3 GB disk0s2
3: Apple_Boot Recovery HD 650.0 MB disk0s3

/dev/disk1 (internal, virtual):
#: TYPE NAME SIZE IDENTIFIER
0: Apple_HFS HD +999.0 GB disk1
Logical Volume on disk0s2
497AE59D-5288-4A37-9945-DBB02BE8046F
Unencrypted

/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 HD 1 2.0 TB disk2s2

disk2 is the one I am trying to mount.


Things I have tried based on varioius advice over internet:
– restaring, changing the usb cable, trying on different computers, restarting in safe mode while HDD connected

– tried to do "diskutil verifyDisk disk2"
results

Started partition map verification on disk2
Checking prerequisites
Checking the partition list
Checking the partition map size
Checking for an EFI system partition
Checking the EFI system partition's size
Checking the EFI system partition's file system
Checking the EFI system partition's folder content
Checking all HFS data partition loader spaces
Checking booter partitions
Checking Core Storage Physical Volume partitions
The partition map appears to be OK
Finished partition map verification on disk2

– Tried "sudo fsck_HFS /dev/disk2s2"
results

** /dev/rdisk2s2
Executing fsck_hfs (version hfs-407.50.6).
** Checking Journaled HFS Plus volume.
** The volume could not be verified completely.

– Tried "fsck_hfs -r -d /dev/disk2s2"
results

Permission deniedjournal_replay(/dev/disk2s2) returned 13
** /dev/rdisk2s2 (NO WRITE)
Can't open /dev/rdisk2s2: Permission denied

– Tried "diskutil verifyvolume /dev/disk2s2"
results

Started file system verification on disk2s2 HD 1
Verifying file system
Volume is already unmounted
Performing fsck_hfs -fn -x /dev/rdisk2s2
Checking Journaled HFS Plus volume
The volume could not be verified completely
File system check exit code is 8
Restoring the original state found as unmounted
Error: -69845: File system verify or repair failed
Underlying error: 8: Exec format error

I am not a professional, and I apologise if those are not logical attempts, just was trying out suggestions I could find over internet.

Thank you so much for your attention and I'd appreciate any help.

 

[MacInWin]

Open Dsk utlity. Click on the "View" button on the top bar of the window, then "Show All Devices." The drive should now appear in the left sidebar with the hardware name. You can try First Aid on the hardware level, but from what you have done already it probably won't work. You will need to reformat the drive, and to do that will erase everything on it.

To do the reformat, select the hardware line in the sidebar, then click on Partition on the top bar, give a name for the drive, select APFS and GUID partition scheme. Let it do what it does and at the end the drive will have mounted under the name you gave it. But it will be totally empty, as I said.

 

[vmvmvm]

Thank you for the reply, MacInWin!
Unfortunately there is data on this HD that I need, otherwise I'd happily try your suggestion.

Thanks again,
VM

 

[krs]

What make and model of external drive is it?
If you have tried everything else, tried different ports and/or different cables and assuming the external is a standard SATA drive with a SATA to USB bridge, I would open the enlosure, take out the SATA drive and mount it in a new enclosure.
I have had two externals fail on me over the years and in each ase it was the SATA - USB bridge that had failed, not the actual drive.

 

[Rod]

krs's suggestion is certainly worth a try if you have the resources. Personally I have never found a way to solve this type of problem without reformatting (erasing) the drive.
You mentioned a Time Machine backup, is there a possibility that the data you mention would be backed up on that?
It's really not a good idea to store unique data on a EHD unless you have a backup of that as well. I think we would all agree that two copies of everything is the way to go.

 

[MacInWin]

In the first post the OP said:

I have a relatively new external HDD that was ejected in some wrong way (possibly when was backuping time machine, or something similar) on a Catalina system.

What I suspect is that the hardware is just fine, in the sense that it communicates, but that the formatting/partitioning information has been scrambled by the improper ejection. In addition, in post 1 the things the OP tried didn't return errors that the drive wasn't there, but that drive was, in fact, there (tested ok for "diskutil verifyDisk disk2" but then failed for various format checks.

This article from three years ago showed the same issue, and the problem seemed to be a corrupted superblock on the drive: How do I fix hard disk "Error: -69845: File system verify or repair failed"

No fix was identified. One poster did suggest their own home-brew inspector, but that has it's own risks and may or may not run or work on newer versions of macOS.

For @vmvmvm, you mentioned Time Machine. Was this drive a Time Machine backup drive? Also, what Mac, and what version of macOS are you running?

 

[vmvmvm]

What make and model of external drive is it?
If you have tried everything else, tried different ports and/or different cables and assuming the external is a standard SATA drive with a SATA to USB bridge, I would open the enlosure, take out the SATA drive and mount it in a new enclosure.
I have had two externals fail on me over the years and in each ase it was the SATA - USB bridge that had failed, not the actual drive.

Hi krs, thank you for your reply. Unfortunately it's a WD elements, and the connection is one piece with the HD, so I can\t try a different cable.

Thanks again,
V

 

[vmvmvm]

krs's suggestion is certainly worth a try if you have the resources. Personally I have never found a way to solve this type of problem without reformatting (erasing) the drive.
You mentioned a Time Machine backup, is there a possibility that the data you mention would be backed up on that?
It's really not a good idea to store unique data on a EHD unless you have a backup of that as well. I think we would all agree that two copies of everything is the way to go.

Hi Rod, thank you for reply.

yes, there is time machine on the drive, but the data i need is in a separate folder on the same volume.

The problem occurred when I was mirroring that additional folder to a second HDD, using FeeFileSync. When I came back it gave an error on one file, which stopped the whole mirroring progress and the system felt crashed, so (if I remember correctly) I tried to force quit and restart.

The mirroring process was canceled in the middle and wasn't complete.

The machine I was doing the mirroring was M1 Mini with Catalina.
The problematic HD has Macos Extended Journaled with both Time Machine and additional data on one volume.
(Catalina let me use it without formatting into APFS, as there was an older time machine backup of other computer)

Thanks again,
V

 

[vmvmvm]

In the first post the OP said:

What I suspect is that the hardware is just fine, in the sense that it communicates, but that the formatting/partitioning information has been scrambled by the improper ejection. In addition, in post 1 the things the OP tried didn't return errors that the drive wasn't there, but that drive was, in fact, there (tested ok for "diskutil verifyDisk disk2" but then failed for various format checks.

This article from three years ago showed the same issue, and the problem seemed to be a corrupted superblock on the drive: How do I fix hard disk "Error: -69845: File system verify or repair failed"

No fix was identified. One poster did suggest their own home-brew inspector, but that has it's own risks and may or may not run or work on newer versions of macOS.

For @vmvmvm, you mentioned Time Machine. Was this drive a Time Machine backup drive? Also, what Mac, and what version of macOS are you running?

Hi MacInWin, thank you for the link.
Seems like in my case it's the same error (69845) but I don't get the "error: failed to read container superblock"


The problem occurred when I was mirroring that additional folder to a second HDD, using FeeFileSync. When I came back it gave an error on one file, which stopped the whole mirroring progress and the system felt crashed, so (if I remember correctly) I tried to force quit and restart.

The mirroring process was canceled in the middle and wasn't complete.

The machine I was doing the mirroring was M1 Mini with Catalina.
The problematic HD has Macos Extended Journaled with both Time Machine and additional data on one volume.
(Catalina let me use it without formatting into APFS, as there was an older time machine backup of other computer)

I also have a macbook pro with Mojave and an older macbook pro with (if i'm not mistaken) High Sierra. and can try things on those machines.

Thank you,
VM

 

[vmvmvm]

I have also tried this method:

which is creating a folder in volumes (sudo mkdir /Volumes/usb)
and then trying to mount into that folder (sudo mount -t hfs /disk/disk4 /Volumes/usb/)

it returned:
GetMasterBlock: Error 2 opening /disk/disk4
GetMasterBlock: Error 2 opening /disk/disk4
mount_hfs: error on mount(): error = -1.
mount_hfs: No such file or directory
mount: /Volumes/usb failed with 1

I wonder if this info can be helpful?

Thanks again,
VM

 

[vmvmvm]

Also I noticed that when the HD is plugged it is not silent, but sounds like some process is gong on on it?

 

[MacInWin]

Hi MacInWin, thank you for the link.
Seems like in my case it's the same error (69845) but I don't get the "error: failed to read container superblock"


The problem occurred when I was mirroring that additional folder to a second HDD, using FeeFileSync. When I came back it gave an error on one file, which stopped the whole mirroring progress and the system felt crashed, so (if I remember correctly) I tried to force quit and restart.

The mirroring process was canceled in the middle and wasn't complete.

The machine I was doing the mirroring was M1 Mini with Catalina.
The problematic HD has Macos Extended Journaled with both Time Machine and additional data on one volume.
(Catalina let me use it without formatting into APFS, as there was an older time machine backup of other computer)

I also have a macbook pro with Mojave and an older macbook pro with (if i'm not mistaken) High Sierra. and can try things on those machines.

Thank you,
VM

I think you meant FreeFileSync, not FeeFileSync, so I did some reading at their website. They do claim it works, and from some of the posts in the forum there, it does seem to work with macOS. However, I suspect that the failed mirroring process may well have damaged the "directory" structure of the drive to the point where it can't be fixed short of a reformat. There are professional services that may be able to rescue your data, but it will be expensive. You can also look at some of the third party recovery tools, also not inexpensive, to see if any of them can recover your data. But I'm not really that optimistic on that because of the TM backups. What TM puts on the drive are not really files, for the most part, but links to files, in chains, from backup to backup until you get to the last time the file changed. In a lot of cases that will be the first backup on the drive. Tools that recover hard drives may not know the difference between files and links. I've never tried a recovery tool on a TM backup drive, and have no idea if anything can be done. Maybe somebody else can help with that particular factor. Add in the fact that there are TWO TM backup systems on the drive, plus whatever FreeFileSync tried to write and the probability of successful recovery goes down. Good luck with it!

 

[vmvmvm]

I think you meant FreeFileSync, not FeeFileSync, so I did some reading at their website. They do claim it works, and from some of the posts in the forum there, it does seem to work with macOS. However, I suspect that the failed mirroring process may well have damaged the "directory" structure of the drive to the point where it can't be fixed short of a reformat. There are professional services that may be able to rescue your data, but it will be expensive. You can also look at some of the third party recovery tools, also not inexpensive, to see if any of them can recover your data. But I'm not really that optimistic on that because of the TM backups. What TM puts on the drive are not really files, for the most part, but links to files, in chains, from backup to backup until you get to the last time the file changed. In a lot of cases that will be the first backup on the drive. Tools that recover hard drives may not know the difference between files and links. I've never tried a recovery tool on a TM backup drive, and have no idea if anything can be done. Maybe somebody else can help with that particular factor. Add in the fact that there are TWO TM backup systems on the drive, plus whatever FreeFileSync tried to write and the probability of successful recovery goes down. Good luck with it!

MacInWin, thank you for your response and for looking into FreeFileSync forums.
As much as I understand from your input, I am in a too deep of a complication.

FreeFileSync worked for me well for quite a while, until this happened. And I think it was because TM started automatically while it was doing the mirroring of the separate folder?
Anyway.

As you suggested I will try to look into recovery tools (like Disk Drill?) and see what I can save.
Luckily, the data I need from this drive is not from the TM folders, but from the separate folder. Not sure, but maybe it makes it easier.

Thanks again so much for your help!
VM

 

[MacInWin]

As you suggested I will try to look into recovery tools (like Disk Drill?) and see what I can save.
Luckily, the data I need from this drive is not from the TM folders, but from the separate folder. Not sure, but maybe it makes it easier.

Maybe. If the directory of the drive, in the superblock, is corrupt, you may have lost all names of all files on the drive. In that case, the files will be recovered as unknown names, probable with some generic filename like "File0001," File0002," etc. You will then have to pick through all of them to find the files with the data you want to save. I've had to do that once before and it was a right royal PITA. I can't recommend any tools for you, maybe somebody else can suggest a good one that works.

 

[vmvmvm]

Picking up files one by one sounds terrifying
Anyways, I will give it a try and hope for best.

Thank you again so much! I will keep you updated with progress.

 

[MacInWin]

It was awful, as the recovery recovered not just the files, but every fragment of every file. There were literally thousands I had to pick through to recover ones I wanted. Took months.

 

[charliea]

Open Dsk utlity. Click on the "View" button on the top bar of the window, then "Show All Devices." The drive should now appear in the left sidebar with the hardware name. You can try First Aid on the hardware level, but from what you have done already it probably won't work. You will need to reformat the drive, and to do that will erase everything on it.

To do the reformat, select the hardware line in the sidebar, then click on Partition on the top bar, give a name for the drive, select APFS and GUID partition scheme. Let it do what it does and at the end the drive will have mounted under the name you gave it. But it will be totally empty, as I said.

Hi there!

Tried your suggestion and this is the message I got:


The operation couldn’t be completed. (com.apple.DiskManagement.disenter error 49182.)

I want to completely erase my external hard disk - I've tried First Aid and
<fsck_hfs -rc -d /dev/diskXsX> without success.

Any other ideas?

Thanks!

 

[MacInWin]

Hi there!

Tried your suggestion and this is the message I got:


The operation couldn’t be completed. (com.apple.DiskManagement.disenter error 49182.)

I want to completely erase my external hard disk - I've tried First Aid and
<fsck_hfs -rc -d /dev/diskXsX> without success.

Any other ideas?

Thanks!

Welcome to the forum.

What version macOS? And can you please send a screenshot of Disk Utility with "View" set to "Show all devices" and the left sidebar showing, please?

What was this external disk used for?

 

[pm-r]

Tried your suggestion and this is the message I got:
The operation couldn’t be completed. (com.apple.DiskManagement.disenter error 49182.)

Maybe give these suggestions and procedures a try:

How to fix com.apple.DiskManagement.disenter error 49218 on an APFS external drive?

If you receive 'com.apple.DiskManagement.disenter error 49218' when mounting or repairing your unmountable external drive in Disk Utility, read this thread.

iboysoft.com

- Patrick
=======

 

[Rod]

You can select the drive and simply try Erase as pictured below.