Unable to access External Drives and Disk Utility after updating to macOS Sonoma.

Unfortunately this happened to me too, three days ago I've updated my iMac Intel 2021 to Sonoma and that broken my WD external hard disk, so it wasn't recognize anymore by any computer. By chance, after trying multiple time with SOS of utility Disk, I've run a recovery software with another Mac (Maverick) that forced to read the damaged HD and get it readable again. I'm now trying to downgrade the computer to the original Catalina. I've spent a lot of hours trying to figure out how to solve this mess and I'm disgusted that Apple released an update so harmful and they didn't fix the issue after months. I will buy a Windows for my next computer.

I did include the name of the app that stopped the ejection of drives as the computer sleeps which corrupts them and makes them unmountable subsequently. This app, available on the App Store, seemed to solve this problem for me but Apple deleted the post giving the name as it is their policy to disallow the naming and recommending 3rd party programs. It seems to me that they need to aknowledge and fix the problem with Sonoma to put an end to this thread of dissatisfaction and frustration. Having to downgrade to Ventura is a lengthy procedure and ultimately we want the upgrades to maintain security on our systems.

Reformatted older Samsung 860 and 870 drives using disk utility. I haven't loaded those drives yet with data, and they are stable. On my brand new WD_BLACK SN770 2TB Media I noticed that it will drop out sporadically, especially if I load the drive up with data. Maybe Sonoma has a hard time reading the control chip when the drive is populated with data.

srajiv wrote:

I thinks Apple has made restriction in using over 1TB external drive in macOS Sonoma, because same enclosure supports 500GB and 1TB MVME SSD but for 2TB doesn't detect the drive after 1st recognise, but the drive works well in Ventura in same machine and other OS.

Please anyone need to find patch or apple will do it future updates

I’ve got a 5TB, three 2TB, and a 1TB drive all running without issue on my Sonoma M1 Mini.

Here I thought maybe my wife had somehow loaded a virus on her 4-month-old Studio Mac running Sonoma.

She's a freelance designer and although I'm no expert, I'm still her tech guy.

We connected a couple 2TB externals set to mirror as a backup plan along with a 4TB external running Time Machine backups. Worked great on her old Mac, why would I think it would be any different on the new Mac? Wrong!

The drives started corrupting starting with the 4TB, then the others.

We lost a ton of time, money, and data; two drives destroyed and $1,000 down the drain recovering some of the data. We can't return the computer and there isn't enough storage internally for her to use it long term.

The really messed up thing is according to this feed Apple has not provided a fix yet.

I'm tempted to switch her to a PC!

One note, even though I couldn't reformat one of the externals affected on an older Mac, I was able to reformat it to Exfat on a PC laptop I have.

If anyone is aware of a solution Apple has provided or a work around to attach external drives without corrupting them please let me know.

Update: OS 14.3.1. Five external SSDs ranging from 1 to 2TB, using AFPS, Mac OS Extended (Journaled) connected through a TB4 4 port hub.

So far everything appears stable day 2. I reloaded all of my audio samples on to one 2TB drive, and it is holding steady. I have used apps that access these samples and they appear to be working fine for me.

Speed tests are within nominal operating limits

Disk Utility reports no errors on any of the drives.

Another information:

During all the time the EXFAT is not showed , The DiskUtility app is completely freezed.

Is impossible to open also diskutil from Terminal.

After 20 minutes the disk appears. And Diskutility app back to life

So is clear . Apple have a big problem with EXfat Drivers.

And no interest to solve.

I never Seen an operating system bugged like this since Microsoft Longhorn.

During all the time the EXFAT is not showed , The DiskUtility app is completely freezed.

Disc utility has done that forever when the format of the drive is corrupt. It may be corrupt “because of the new file system driver for ExIt may be corrupt “because of the new file system driver for ExFAT, but it is nothing new for disk utility

So upset.

Running a M1 macbook pro, I do animation and filmography so my internal drive is usually a working drive. I have many various sized portable HDD/SSD's I store projects and personal files on. One of which contained all my photos, only partially mirrored on another drive. All in all I lost a 350gb photo/video library the entire duration of my wife and my relationship, the least important but still heartbreaking was many backed up movies and music library including my pesonal Ableton music projects, plus several thousand PDF and Epub books I have collected over the years.

Never had an issue prior to updating to Sonoma. I tried doing first aid on the drive when it first stopped responding and the drive label went from "Nvme2tb" to "Nvme1 2(insert random character)N" I grew very concerned and attempted file recovery , dropped $$$ on software to attempt to fix an issue I never had before. Upon "successful" recovery, I was greeted by 100% of my photos showing mostly grey, every video corrupted beyond recognition and a massive negative flood of emotion as my heart sank upon the realization that I have just lost a massive part of my history. 1.65 tb of media and documents, poof.

"ShOuLd HaVe ClOuD bAcKuP" I hear as I write this issue. Fact is I do have a library backed up in the cloud, just not THAT one as it contains sensitive information/documents I don't want on the cloud. Plus the sheer volume of data I work with is not feasible to store on the cloud.

I can stand losing a 1tb drive with client/project files, I wasn't so upset about that, at first I thought It was just the drive, but when I started to back my personal stuff I wasn't expecting to lose it all.

This is beyond money, and all because I thought apple software was stable. Had I known there were such bugs I never would have updated. Trying to carve out time to downgrade so I don't have this issue anymore.

ps: First post deleted since mentioning something legal, suspicious.

I have a HighPoint external Thunderbolt drive that the company supplied me with updated firmware and a driver for so that it would work with Sonoma (2 SSDs and 2 HDDs installed in it). And it did — until it didn't. I used it this morning, and a little pop-up said it might not work with future OS updates but it did still work this morning — until I ejected it and then later tried to use it again — now, nothing. It's not even registering on my M1 MacBook. Really frustrating, and I am wondering how many enemies Apple is willing to make by not fixing this problem because it sure isn't making any friends by not resolving this issue.

I've had some strange things happen with MacBook Air M1 running Sonoma 14.1.1 in the UK. I don't see any later release available so can't upgrade.

Firstly a SanDisk MicroSD 128GB ExFAT that I used in my dashcam became corrupted on my Mac - the device appeared to be empty and lost it's NEXTBASE label. I was able to use Photorec but most files were corrupted which was disappointing. Both lost a 128GB disk image and now have missing files.

In trying to fix this two 2TB SSD drives a Crucial X8 and X9 also formatted as ExFAT both would sometimes take a while to mount in Finder but appeared to work until recently when both have been corrupted. I would unmount in Finder only to find they were uncleanly removed.

So could be a coincidence but my spinning (non-SSD) drive that is ExFAT appears to be working OK.

Would be interested in an explanation... I've lost all faith in using those drives on the Mac. Thanks

HAd to power down yesterday...

Didnt think anything of it as i have had to restart a BUNCH lately..and somehow was devoid of external HD issues...

or so i thought..

Upon the restart of the computer ALL of my external drives were GONE.

Took the USB HUB, mounted on my Monterey machine...NO DRIVES MOUNTING..

Remembered a post about going to Windows , did that and the drives are now back on Sonoma 14.4.

What the heck is going on ?? Unreliable OS that chooses to either see or ignore drives....

[Edited by Moderator]

Cannot believe it's April 6th 2024 and still Apple has not corrected this major problem with Sonoma that's been going on for 6 months. I'm a professional photographer & videographer and dropped 2k on one of apples new M3pro computers in January, which is marketed towards people in my profession, and have been having issues mounting my crucial SSD ever since I got the computer, which prevents me from doing my work basically rendering the computer useless to me. Every so often the drive will mount again randomly but if I unplug it or restart my computer then it will not mount again. Currently cannot get it to mount, have tried every troubleshooting idea I've been able to find. The data is recoverable luckily, which I found using Disk Drill, but the drive will not mount to be able to use it. There's no way to install an older OS on these M3 computers. Almost anyone who's buying an M3pro for its intended professional purposes would be using SSDs and running into the same issue. Unbelievable.

annabellerama wrote:

So what is everyone doing when their external drives and Time Machine backups are no longer available??

*I need to know because that is exactly the situation I am in…

I’d verify my other backups and then erase the bad drive and try it again.

this has been incredibly frustating to me too! I have a samsung T7 SSD and noticed that my mac would not reliably read it after upgrading to sonoma software. I couldn't think of any other changes, but did not suspect that a software upgrade would have caused this problem. After reading several forums, I am shocked that this is a common issue from a macOS software UPGRADE. it's embarassing that apple pushed an upgrade that created problems rather than solving them.

Nowadays, I just plug in my ssd and wait 30-40 minutes for it to randomly show up on my homescreen...

the same drive is immediately recognized by windows systems.