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

I had to reformat all of my older SSD 2.5" removable drives after I migrated to Sonoma. The newer intel stick drive didn't need to be reformatted. Using APPS.

The USBC powered HUB seems works also for me, only on the first port.

I am having EXACLTY the same issue!

When I shut down the computer or reboot it takes ages to mount, this only happens when the mac reboots or shut down, I know this is normal behavior when you unplug a hard drive without ejecting correctly, but now is happening every time I boot or restart the Mac.

If eject the drive on macOS and plug in again it shows up instant, but if shut down the computer takes ages. It seems its going like a process to check up if everything is okay with the drive and then it mounts, At the moment I find that the best solution is to eject the disk manually in macOS before restarting or shut down. if I do this it appears instant on reboot or start up

I read the notes on the update. It refers to fixing issue about encrypted drives not mounting. None of my drives that failed to mount were encrypted. So I'd say Apple still hasn't dealt with the exFAT problem.

I am still having the problem on 14.1.1 that when I shut down or reboot the Mac, the drives on boot up only show up after a few minutes meaning that they were not ejected correctly! When it is a shut down or a reboot.

this again, not happening on Ventura with the SAME drives. On Ventura they appear instant after boot up

@r_e_d_oo 's suggestion worked for me with WD passport external hard-disk. I use a M1 MBPwith Sonoma. External hard-disk got corrupted twice while restarting the computer and wish I had seen this post the first time it happened so that I could have saved money buying the second. It is certainly infuriating and would love to know what's going on that makes this happen. Well, at least the problem can be reliably reproduced and easy enough for Apple engineers to identify. Since there must be a lot of users encountering this problem just by account of all the blogposts out there discussing the topic, hope Apple would find a fix for this issue.

My small 2TB WD exfat hdd, suddenly come online this afternoon. Visible in disk utility and terminal; although it won't let me run first aid upon it. I have forensic software pulling all the data I can at the moment but it looks as though it's going to be a long drawn out process. So as soon as anything is pulled off it it loaded up to the cloud as well as putting a copy on my local disk.

I tried running diagnostics and repairs via terminal but it won't allow me - it tells me there is no GUID format on the disk; yet in disk utility confirms it has.

My big 8TB seagate hub is still offline. It's sitting there looking at me in system profile under the USB bus and when I run terminal ioreg -p IOUSB it surely is under the root directory of everything attached to the USB ports.

oneilw@Drs-iMac ~ % ioreg -p IOUSB

+-o Root  <class IORegistryEntry, id 0x100000100, retain 29>

  +-o AppleT8103USBXHCI@01000000  <class AppleT8103USBXHCI, id 0x100000507, registered, matched, active, busy 0 (14269 ms), retain 125>

  | +-o USB2.0 Hub             @01100000  <class IOUSBHostDevice, id 0x10000089d, registered, matched, active, busy 0 (14182 ms), retain 35>

  |   +-o AX88179A@01110000  <class IOUSBHostDevice, id 0x1000008ab, registered, matched, active, busy 0 (2915 ms), retain 32>

  |   +-o My Passport 25E1@01140000  <class IOUSBHostDevice, id 0x1000008ad, registered, matched, active, busy 0 (4644 ms), retain 26>

  |   +-o Expansion HDD@01120000  <class IOUSBHostDevice, id 0x1000008cb, registered, matched, active, busy 0 (7570 ms), retain 25>

  |   +-o Expansion HDD@01130000  <class IOUSBHostDevice, id 0x1000008e3, registered, matched, active, busy 0 (7481 ms), retain 25>

  +-o AppleT8103USBXHCI@00000000  <class AppleT8103USBXHCI, id 0x100000380, registered, matched, active, busy 0 (138765 ms), retain 93>

    +-o One Touch 8TB Hub@00200000  <class IOUSBHostDevice, id 0x10000ba23, registered, matched, active, busy 0 (46328 ms), retain 30>

    | +-o One Touch 8TB Hub@00210000  <class IOUSBHostDevice, id 0x10000ba44, registered, matched, active, busy 0 (46304 ms), retain 23>

    +-o One Touch 8TB Hub@00100000  <class IOUSBHostDevice, id 0x10000ba34, registered, matched, active, busy 0 (6 ms), retain 29>

The extent of my programming and coding skills, stop way back when we just had basic and ms dos, I'm stuck if anyone can point me in the right direction it would be appreciated.

Just in passing looking back on archives there seems to have been a problems as far back as 2018 and maybe farther with ext hdd's not unmounting properly and the drives were then not coming back online again.

I'm an historian - I know history repeats itself, although maybe this has never been sorted out.

This also fixes the problem when you plug the drive into another Mac. I ran First Aid on it, it fixed a few things, then it worked again in the first Mac.

I have not verified that the corruption happens when shutting down. But I will watch for this. I had two drives go bad in two days - I knew that couldn't be a coincidence.

Following - similar issue. I'm unable to even download graphics from Canva to my external HD now. I have to download to my Mac, drag it over, then delete it off my Mac to save space. I was fine with my old computer and my mom gifted me a new MacBook Pro 14" with Sonoma, but it has now caused me so many issues with my external HD. I've changed permissions to Read & Write for the entire volume. I've added admin read & write access through every folder. Now all of my Premiere Pro video editing templates cannot be opened because it's either saying it needs to be converted from a previous version of Premiere, then says all of the media is offline not allowing me to locate it even though it has the correct path. So much frustration. Debating bringing it into the Genius Bar but based on this forum it seems they're not even aware of this issue? I refuse to format and lose all of my data for the past few years.

Disk Utility:

Mac OS Extended (Journaled)

4 TB

Even running first aid says: Operation failed because volume could not be unmounted. Restoring the original state found as mounted. Unable to unmount volume for repair.

Help!

Those who are able to get windows to run a repair of their drives are they all exFAT or MS Dos (FAT); have any other users who have used apple extended and APFS been able to recover theirs?

Apple have had a problem dating back to around 2015 with external drives and them dropping offline. I noticed on my iMac M1 on Christmas Eve I was plugging in a usb c adaptor to the thunderbolt port and it arced, which was worrying. I didn't have much else to do on Christmas Day so I started looking into if there had been similar problems in the past. In 2012 complaints went out about usb ports sparking, which would indicate poor earth contact or grounding as some may know it as.

This problem was still going on until 2015 with the update of Monterey 12.5, when they issued a software patch - how does a software patch stop a computers usb hubs from shorting? Apple has refused to admit liability; it may well be another class action suit, just like the broken screen on the MacBook Air which has been going on for years. They have now kicked it back to the Plaintiffs wanting more evidence.

What is annoying me is that you see all these promoters on 'YouTube' and the like pushing the products with too many new iPhones , Mac computers and freshly manicured finger nails and not one has said we have a problem.

Anyway I removed Sonoma and reinstalled Ventura, Ive had enough. This computer has cost too much money, in having to replace external drives and maintain separate cloud storage as I no longer feel I can trust it.

A thought, when they updated Sonoma the IPSW (firmware) was updated, could this contribute I wonder?

Looks like Tim's head might be on a platter soon the way things are looking at Apple.

Bought a new Macbook Pro M3 Pro with Sonoma a few days ago. I plugged in my Crucial X8 external SSD and everything was fine until I disconnected it without the safe removal. I did the Windows repair trick and now it works again, but everytime I plug it out without ejecting or I restart my Macbook I got the same issue over and over.

I have the same issue! i connect exFAT external drive to new macbook nov. 2023. via usb-c to usb-a cord. The computer finds the drive. i work then eject properly. IF i try to connect drive again, it is not able to be found.

another computer running windows, finds an error and runs repair to fix. The drive can connect again, but only to not work again after another window repair. PLS fix this issue

Use softwareupdate in Terminal.

To list available installers:

softwareupdate --list-full-installers

To download a specific version,

softwareupdate --fetch-full-installer —-full-installer-version 13.6.2

You can create a boot usb stick from terminal, can you download the version of OS you need?

Im not sure what the full terminal command is but it’s not hard to find, asking it to fetch all the software updates should list those compatible versions with your mac.

When you are in recovery and you are asked to download the OS, I assume it only wants to give the last version of Ventura or perhaps the version you were shipped with.

So many updates…

I am on macOS Sonoma 14.2.1 and my external 1TB SSD SanDisk drive is now unreadable. This follows the upgrade from Ventura.. my iMac never had issues with the drive until the upgrade two days ago. Drive was formatted ExFat..