Hello everyone,

I'm having a little issue with mounting my external hard drive lately. I've tried quite a few methods in hope of getting it to work again, but so far, no luck. I hope someone can help me solve this issue, or those who have the same problem may also share your insights.

My external hard drive was working fine about a week ago. But one day, I ejected the hard drive and the icon disappeared, so I thought it was safe to unplug it. When I did, it said the hard drive was not properly removed. It still works fine when I use it the next day, but the same thing happened. It said the drive was not properly removed after I ejected the drive, waited for the icon to disappear, and then unplugged the drive. After that, it never works again, and the attached images are the info I got when I tried to mount or run first aid on this drive.

Please help & thank you in advance!

Computer: 27" iMac - MacOS Monterey

External Hard Drive: WD_Black 4TB. APFS encrypted

I have the same problem. External SSD drive for Timemachine, APFS formatted. Creating the initial backup worked, then was running for some time and all of a sudden it can't be mounted anymore. Might be that it occurred after a reboot, I usually never reboot my Mac.

The same external drive was working before Monterey smoothly for over a year. After the update the Timemachine backup could not be finished because of some strange file conflict. Whatever, I reformatted everything and started from scratch and now I am in this new situation.

I think there is a sever bug somewhere in Monterey.

Same problem. External SSD for Time Machine, APFS formatted. Lost access with Monterey and can't get it back.

I did find this:

https://developer.apple.com/forums/thread/680500?answerId=676624022#676624022

Not formatted in ExFAT (APFS), but after entering command was prompted for password but had no ability to enter ($ sign was pre-entered.)

Same issue with my drives…. I had an external drive for my pictures and I could not access it. I tried saving it through terminal with all the commands i could think of…. Nothing really helped. In the end i capitulated and bought „Disk Drill“ to access my files.

Then i loaded all the pics on a new external drive and about two weeks later the same error happened. I am afraid, Monterey has a weird bug.

I had this happen 4 TB WD My Passport on Big Sur 11.6.2, the 1 TB partition for my Time Machine didn't come up and mounting gave the "disenter error 49218". Here's what worked for me (at least for now):

https://developer.apple.com/forums/thread/680500?answerId=676624022#676624022 "Try to mount the disk, and switch to Terminal and write sudo pkill -f fsck "

Attempted to run First-Aid on that partition.

Restarted the computer.

Time machine came back after that. No clue which of the steps may have actually fixed it. Will find out the next time that this inevitably occurs.

This worked for me too:

https://developer.apple.com/forums/thread/680500?answerId=676624022#676624022%C2%A0%22Try to mount the disk, and switch to Terminal and write sudo pkill -f fsck" Attempted to run First-Aid on that partition. Restarted the computer.

I agree it's a weird bug with Monterey. I ran into the same issue with my external Samsung 4TB SSD. After I upgra ded to Monterey my drive immediately started acting weird and then I received this message "Could not mount “4TB SSD”. (com.apple.DiskManagement.disenter error 49218.)" I've tried all kinds of software including Terminal to force mount and I'm still unable to mount this external drive. I have over a decades worth of family photos in iPhoto on this drive most likely all lost. Thanks MacOS Monterey!

I unplugged a 1TB SSD without ejecting it first, and when I connected it again sometime later, I couldn't even see it in Finder.

I opened Disk Utility and run first aid on it and got an error (com.apple.DiskManagement.disenter error -119930878.) but after I closed it, it continued running and some minutes later, the drive was fixed and I was able to see it in Finder and use it again.

I'll remember to eject the drive properly next time before unplugging it.

I have the same issue on iMAC 27' 5K running Monterey.

Used to have multiple external hard drive hooked up to my USB ports, now cannot do this.

As a professional photographer this is death for me. I can no longer upload my photographs to my MASTER external drive then edit them to a seperate external drive to deliver to the client.

I tried going into terminal. I tried turning off the MAC disconnecting power and waiting then reconnecting USB devices. I tried disk first aid.

I have over 30 external hard drives ranging for 1 TB to 14 TB and I'm going CRAZY!!!! HELP

Ok, I had this same issue and found a fix. However, it's ONLY a fix if you do not care about what is on the external HDD. Open Disk Utility and hit Partition. Change it to APFS (Encrypted). I hit "Apply" and it warned me that all data would be deleted. I said ok. It wiped it and then it automatically mounted and all is well now.

Mine was previously on APFS (case sensitive) and I had all of the same issues you all have had and none of the suggested fixes did not work.

FIXED! I've had trouble accessing my external LaCie time machine drive for a while now and nothing I had found online has helped. Couldn't mount it, erase it or use first aid on it. Would get failed messages non stop. The only solution that has helped I have, fortunately, found was by this guy on youtube, https://www.youtube.com/watch?v=Z9y1oRYlmh0 . Formatting the container within the disk utility to a MAC OS Journaled had worked and I was able to access the partition anew and then restart the time machine.

I am no developer, but was reading these forums and thought of posting this in order to, maybe, help some of you.

I'm having the same problem with my MacBook Pro M1 max. I have a 2TB external drive I was using with Time machine backups that I can No longer mount. Even disk utility won't allow the disk to be erased and reformatted. I would have thought that apple would have the solution by now seeing how so many have encountered this problem. can someone please help????

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