Disk Utility & External Drive: "could not mount (com.apple.diskmanagement.disenter error 49218.)"

Continued:

last but not least - terminal gave no insight either.

https://discussions.apple.com/content/attachment/95fd90df-c906-4dc4-b408-fac8fa533d96

The first two commands shown beginning with "ps" is showing the running processes and filtering for the "fsck" process....the "fsck" process was not active at the time since the only result returned is the processes searching for the "fsck" process. The other "pkill" commands are worthless since "fsck" was not running at the time.

Again, don't run any Terminal commands without at least having a basic understanding of what those commands do. Many commands offered online may have multiple commands pieced together like the ones you presented here. It is easy to search online to learn what each command does, plus you can usually read the information manuals for each command yourself by using the "man" command in the Terminal app. For example, to understand what "pkill" does you would use the following command to read the manual pages for it:

man  pkill

Same goes for "ps" and "grep", as well as "sudo":

man  ps
man  grep
man  sudo

The vertical bar " | " is called a pipe which connects two commands together. The output of the first command becomes the input for the next command after the vertical bar. There are a lot of sites out there explaining the basics of the command line....while most of them will be for Linux, the basics mostly apply to macOS command line as well although many of the same shared utilities on macOS are typically more limited because they are using older outdated versions of the utilities. Here is a macOS specific tutorial and introduction:

https://scriptingosx.com/2017/07/first-steps-in-terminal/

I REALLY don't wanna lose my backups and although I do have EaseUS recovery software, I don't know if It would work given the nature of the drive state. Any suggestions please??

I don't know how data recovery apps will work on a TM backup volume.

Are your TM backups encrypted? If so, then you probably won't be able to do any scans with recovery apps.

I believe the TM backup volume is now read-only, but you may want to use the command line to manually mount the volume as read-only. I doubt this will make any difference though. Assuming the volume is not encrypted the command would be something like this, but you must adjust the drive identifier to use the current drive identifier since it can change each time the drive is reconnected to the Mac. Using the information in your screenshots, the drive identifier for your TM backup volume was "disk4s2":

diskutil  mount  readOnly  disk4s2

If there are no errors, then the volume should show up under "/Volumes".

Another possibility is to try to mount the APFS backup snapshot instead of the complete APFS default volume. This is harder to explain as you must first see if there are indeed accessible APFS snapshots within the Container, then pick the correct one to mount (I believe they have the date & time within the snapshot name). Here is an article about APFS snapshots...be careful.

https://derflounder.wordpress.com/2019/05/08/creating-managing-and-using-apple-file-system-snapshots-for-startup-drive-backups/

In the end you may need to resort to your other dedicated backup drive.

Or if the data in the last backup is extremely important, then you may want to contact a professional data recovery service such as Drive Savers. Drive Savers provides free estimates and are recommended by Apple and other OEMs. If the data is critical, then I highly recommend you choose this option now so you don't put the data at further risk.

So, just to confirm that either the Logic Board was replaced or Apple performed a clean install of macOS during the repair?

amilam821 wrote:

All of my backups are saved to a volume on a Cirago USB 3.0 External Drive and I have one Volume as ExFAT and one as Mac OS Extended Journaled because I use it between a Windows desktop and my Macbook Pro. I also had a smaller volume that was used strictly for backups.

FYI, just an aside here.... I never recommend partitioning any drives as it usually creates problems at some point usually because the user realizes one or more of the partitions does not have enough room. Fixing this usually involves starting over from scratch risking the data and taking time.

Having a data partition on a drive used for backups is risky as it puts the backups at more risk of accidental damage. Sharing with a Windows' system increases the risk tremendously as you now have another OS operating on a drive holding precious backups.

It is good you have another dedicated backup drive though.

I was backing up everything via Time Machine right before leaving the computer at an Apple Store to get the USB port replaced and it kept getting almost towards the end of the backup and all of a sudden it would stop saying that the volume was ~1.5GB short to finish the backup at like 93%. I had to eventually close time machine

I'm not sure how the TM backup transfers work, but I believe they utilize APFS snapshots. If TM transfers the entire APFS snapshot, then interrupting it may be fatal for that snapshot. When the third party app Carbon Copy Cloner (CCC) performs a clone of recent macOS boot drives it must resort to using the macOS "asr" utility which appears to stream the APFS snapshot to the new location instead of copying files individually.

When you prematurely ended the transfer through the Time Machine app, did TM present any messages?

Similarly, I tried running first aid on the volume and the parent container and both check out fine but don't do anything.

Try running First Aid on the physical drive in case there is a problem with the partition table.

I tried using Terminal to input "sudo pkill -f fsck" because I read that this can fix even non ExFat issues with it, but alas it nothing.

You need to be careful running Terminal commands you find online if you don't understand what they do...especially commands beginning with "sudo" as it gives the command root/admin privileges that can potentially do great damage to the system since even a simple typographical error could completely change the operation of a command.

As for the command mentioned here, this will terminate a file system check run by "fsck" utility if that utility is currently running a process. If you are not running a current "fsck" file system check, then this command will do nothing. The only reason to run this particular command is to attempt to terminate a stuck file system scan.

What I think is interesting is the line about APFS versions 1934 vs 1677; I have no idea what this would indicate. I also don't have any idea what "Exit code of 0" means.

It means you are using a newer version of APFS than that which originally created the APFS volume on the external drive...this is a good thing since newer versions of the APFS tools will understand older versions of the APFS file system.

"Exit Code 0" means the command completed without any errors.

HWTech wrote:

amilam821 wrote:

All of my backups are saved to a volume on a Cirago USB 3.0 External Drive and I have one Volume as ExFAT and one as Mac OS Extended Journaled because I use it between a Windows desktop and my Macbook Pro. I also had a smaller volume that was used strictly for backups.

FYI, just an aside here.... I never recommend partitioning any drives as it usually creates problems at some point usually because the user realizes one or more of the partitions does not have enough room. Fixing this usually involves starting over from scratch risking the data and taking time.

Having a data partition on a drive used for backups is risky as it puts the backups at more risk of accidental damage. Sharing with a Windows' system increases the risk tremendously as you now have another OS operating on a drive holding precious backups.

It is good you have another dedicated backup drive though.

Another thing to add here is how are you backing up the data on the other two data partitions? If the data is unique to this drive, then you need to back it up somewhere else since including it within the TM backup on this same drive is risky since a drive failure would wipe out both the original copy and the backup copy. This is something many users don't realize when they share a backup drive with a data drive.

Plus, if you need to share a drive between macOS and Windows, why not just use exFAT for the entire data drive as it saves having multiple partitions which I've already mentioned causes problems for many people at some point. Just make sure to use Disk Utility to erase the drive as exFAT since Windows may use a file allocation size with exFAT which macOS does not recognize unless you can select a macOS compatible file allocation size when formatting the drive under Windows.