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

I have had issues as well with external drives formatted as Mac OS Extended. I have a Mac Ultra, so I should NOT be running into speed issues at all, but I get slight lags when accessing files from the external drive, and this was not happening until I upgraded to Sonoma. The lags can be long enough at times that I'm actually sitting and waiting. It's quite annoying.

Would love to know if you find solutions (other than reformatting lots of drives LOL)..

Amy

Let's face it, Apple doesn't want you buying any equipment from anyone but Apple. They made our drives unusable. Their solution is for us to buy a new mac with a larger hard drive. I may just go back to my linux box.

MikeyBee123 wrote:

Let's face it, Apple doesn't want you buying any equipment from anyone but Apple. They made our drives unusable. Their solution is for us to buy a new mac with a larger hard drive. I may just go back to my linux box.

I have several USB and two Thunderbolt enclosures and haven’t had any problems with any of them on Sonoma. I don’t use ExFAT much, but no problems there, either. I also transfer files on FAT32 flash memory and SD cards.

There has got to be some other issue involved besides Sonoma.

Just lost another disk - Western Digital format exfat.

First disk was 8TB APFS Time Machine Disk.

I hope everyone has RAID disks set up, for disaster recovery. I expect something like this from a PC with windows but not a Mac.

Methinks this iMac will be sent back to Apple - under the Sale of Goods Act - It does do what says on the tin!

I just wanted to follow up on my previous reply about having slowness problems.

I use an OWC Thunderbay Mini external drive exclosure (not set up as RAID) for SSD drives. I talked to OWC to be sure there are no known issues on their end. There are not. I had no problems before upgrading to Sonoma.

Because someone else in this thread mentioned that the way the drives are formatted, including Mac OS Journaled, could be causing the issue, I decided to reformat the drives. This required moving stuff around and making backups, but I took the time and did it.

My drives had been formatted for Mac OS Journaled.

I erased and reformatted them to APFS.

My problem is gone. It is a night-and-day difference.

Just to reiterate, I had NO ISSUES before upgrading to Sonoma. It wasn't a drive going bad because it happened across all external drives. The problem was slowness and lagging when trying to read the contents of any of the drives. All were formatted to Mac OS Journaled. Now formatted as APFS the problem seems to have gone away.

Well I've just bought two new drives, one for Time Machine and then the other for my irreplaceable music library and misc. files, and research materials. I've also upgraded my cloud storage.

The Time Machine has automatically formatted to APFS (Case Sensitive) encryption, the other Mac OS Journaled (extended).

I hope not to have another problem like this again, well at lest my cloud storage will have a full year of backups this time. The amount of research lost.... I could cry!

Have you tried plugging your old drives into a Windows PC?

Sonoma didn't read mine properly, but the WinBox didn't have an issue.

Ended up running freesync to compare the two drives with windows (its the same content, the 60TB was/is filling up, so I got the 88TB for the extra room) when I determined the 88TB and 60TB were the same, I killed the 88TB, formatted it as APFS and copied the 60TB to the 88TB, and then I used DirEqual to check that the 88TB had the same as the 60TB, formatted the 60TB and copied the 88TB to the 60TB so I'm back to both drives being the same, and both being APFS, then I purchased a copy of Paragons' APFS+ for Windows in case I need to use one of the drives in a windows environment.

Thanks Uncle Tim...

I have a 16TB WD enterprise-class external drive, I connect it to the Sonoma system via an external USB 3.2 casing, the drive is often not recognized by the system and the disk utility application hangs while reading and scanning it. The only thing that helps is connecting to a PC and a system, e.g. WIN 11, and scanning and repairing the disk. And then I connect it to the MAC computer and the disk is visible. I have the impression that it is the Sanoma system's fault and that it somehow damages the disk, but repairing it under Windows helps. The disk is then visible for several connections and then it is invisible to the Sanoma system again. This relationship occurs on my AIr with M1 and iMac 27 2019. EXFAT file system

I’ve had problems with WD Passport 5TB and Sonoma. Tried every different way to get it to work. Took it to local IT shop after he could not sort it out whilst sharing my screen. Worked seamlessly with his older macOS. Got it back home and could not get it to work despite IT guys help sharing screen again for best part of an hour.

I had the same problem, but I found a solution. Using the Disk Manager in Windows, I reformatted the disk with ExFAT filesystem, but with Allocation Unit Size set to 128k (don't choose Default, which is 1024K in Windows). After that, the disk will mount in Sonoma (I'm running 14.1).

See: https://iboysoft.com/questions/is-there-any-way-to-fix-an-exfat-drive-not-mounted-on-mac.html

Hello,

Just found a solution; if you have exfat external hdd and you're trying to connect it with an usb type a to type c adapter, it does not work.

I just bought new usb type c to micro b cable and connected it directly to mac, it works like magic! :)

What a shame that Apple doesn't know how to connect the ports we purchased from them for peripherals. Could it be they don't want to know? The USB protocol must be very complex -- too complex for Apple engineers.

@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 FAT external SSD drive is being detected very slowly when boot up. When MAC will fix this problem? It makes me really angry about that. The latest problem of Logic loading UADx plugins have been solved after update. This is good. I hope Apple will solve the external FAT format drive issue as soon as possible.

The problem has been ongoing since the introduction of the new system and has not been resolved yet. Every time a new patch appears, I worry whether I will go backwards with the system or lose data again. Because something is wrong again. It has long been known that there is no full compatibility between PC and MAC systems. As for EXFAT files, if I format the disk to macosx, after connecting it to any system older than Windows 8, I want to repair it. Something is wrong here when we talk about new processors, and every time there is an update, a new conscious user must make backup copies