In order to replicate the issue just connect any external SSD wait for a while and it will be disconnected with message "Disk Not Ejected Properly". SSD is connected to M1 MacBook Pro. It's neither a cable issue because I tried multiple cables, nor an SSD issue as everything worked just fine before upgrade.
Drives like the MyBook came with software, and the manufacturer suggested you install that software.
What that software does is to "spare you the annoyance of having to re-initialize the drive" from its factory set Windows New Technology File System (NTFS, the W is silent because there are no other Operating Systems) or similar unusual (on a Mac) format. Instead, the software they provided would simulate a MacOS drive inside an NTFS file for your Mac.
The downside of using the manufacturer's software is that if the manufacturer's software is not loaded, the Macintosh Volume may not be readable, or may not be writable. This means that in startup manager, Installer, and in Recovery such as after a data loss, the Macintosh Volume may not be visible.
The standard advice given here to all users, including novice users, is to discard the manufacturers software and NEVER use it. "Best Practice" is to erase the physical device when new, using only MacOS Disk Utility, and create the fundamental data structures needed for consistent, reliable use by MacOS.
Be sure to "show all devices" which will allow you to ERASE the entire Physical Device by its immutable manufacturer-given device-name, not just user created Volume-name such as ‘Macintosh HD’.
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The litmus test for 'what format is that drive' is to run this Terminal command, and look for the NAME of your drive in the list. This is the output for an Apple File system drive, first for the (Physical), then for the (synthesized) APFS container-scheme:
diskutil list
...
/dev/disk6 (internal, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *240.1 GB disk6
1: EFI EFI 209.7 MB disk6s1
2: Apple_APFS Container disk7 239.8 GB disk6s2
/dev/disk7 (synthesized):
#: TYPE NAME SIZE IDENTIFIER
0: APFS Container Scheme - +239.8 GB disk7
Physical Store disk6s2
1: APFS Volume X14-SSD240 97.5 GB disk7s1
2: APFS Volume Preboot 26.5 MB disk7s2
3: APFS Volume Recovery 507.6 MB disk7s3
4: APFS Volume VM 20.5 KB disk7s4
my MacOS volume named X14-SSD240 is on a physical SSD drive about 240 GB in size.
The only thing I know, is that the issue appears since I've upgraded to Sonoma and only when I use nvme drive. My machine is m1 MacBook Pro, and I've never experienced such issues with intel mac's. When I use slower ssd's 2'5 + external enclosure -> everything works fine. Not sure whether it's a hardware or a software issue but it's somehow related to thunderbolt ports.
Also, the link to his feedback doesn't work because those reports are "tied" I think with one's Apple ID...so they cannot be made public, I think.
Here you can see mine:
Just make sure to include as much details as possible and submit it. Please! :) Your report is really helping me, and you, and everyone with this bug / problem! Thank you!
Same issue MacBook Pro MP1 running Sonoma 14.2. I thought it was issue with my Samsung T7 Shield 4Gb SSD (which did die once and was replaced by Samsung), but the second unit had this issue over night when the computer would go into standby. Sent the second T7 back and Samsung reported nothing wrong with it. I noticed the same issue happening with a Seagate 5Gb HD. I've gone through settings to basically keep the computer nearly fully-on at all times and never let drives go to standby... still happens. For sure seems like a Sonoma issue.
hi! I bought a new enclosure and new m.2 ssd this weekend. Tried getting it to work with my Sonoma machine, didn't work. Plugged it into my Monterey machine, zero problems. It's a Sonoma issue...
Formatting my drive and starting over from scratch appears to have fixed the problem.
I tried all of these options except changing the enclosure and none of the really helpful. It is not a coincidence that in Venture everything works fine. So the issue is on apple side and I raised a bug to fix it.
Yeah.
Almost the same problem.
Running M1, everything was smooth until I updated to Sonoma.
My problem is that I usually edit videos with files on an external SSD, it lets me edit everything well, but when I try to export something to the SSD, it completes the process, but, I cannot see the file on Finder, same problem with downloading anything from Chrome to the SSD directly, cannot find the file, then, I disconnect the SSD, connect again and voilá my files are in fact, inside the SSD.
So, it's very annoying to work like this, connecting and disconnecting the SSD constantly.
I work in a similar way, editing photographic files on an external SSD. I have also experienced exactly this on Monterey, reported it as an issue with the thunderbolt four slots, was told its software not hardware (which I still doubt), and was forced to upgrade to Ventura but the problem persists. It extends beyond files not displaying in Finder: I find images also don’t display properly in photographic applications such as Photoshop, Lightroom, and InDesign.
Same issue here... 4TB SSD external hard drive working fine on my macbook pro 2021 until the update. Tried multiple cables (Angelbird, KondorBlue, Kingston) no luck. Works fine on windows. I edit videos off of my SSD and this is a nightmare.
What OS were you on before? I'm interested because I was (maybe still am, not sure) convinced this was a hardware (ports) issue on my Mac. I've had the identical issue on both Monterey and Ventura, but it's not just SSDs, it's my RAID and 2 x 7200 rpm backup drives as well. It stopped completely for several months after all 4 USB-C/thunderbolt slots were replaced. I stayed on Monterey but the problem gradually returned. Mac has been sent for twice since then. Last time they replaced the logic board and internal SSD but not the ports and upgraded OS to Ventura (I refused to agree to Sonoma because of all the issues I see reported here). However the problem continues on Ventura. It's less frequent than before, but definitely not cured.
Like you I do all my processing (photographer) on external SSD and this is a nightmare. (Also a nightmare for backups of course).
It's also not a coincidence that so many people have described it happening on multiple drives – including me (4 external drives, different models, different ages). Like you I've done the dance with cables, removing hubs etc. I also have various other issues including problems with dictation, which Apple genius bar diagnosed as being due to intermittent (wired) Internet connection via Thunderbolt ports. I'm still having this problem although I have yet to upgrade to Sonoma. I don't know enough about the relationship between hardware/software/firmware but I can't help thinking there is something else at play because it is not just Sonoma.
When you post here, Readers are other users like you. Apple does not troll the forums looking for issues. Apple does not understand the urgency of this issue unless a LARGE number of Users let them know it is an issue.
Be sure you have either contacted support here, in hopes of getting more help:
or posted a product feedback of type "bug report" here (but these are Not tracked and no response will be forthcoming):
When you post here, Readers are other users like you. Apple does not troll the forums looking for issues. Apple does not understand the urgency of this issue unless a LARGE number of Users let them know it is an issue.
Be sure you have either contacted support here, in hopes of getting more help or creating a Bug Report:
or posted a product feedback of type "bug report" here (but these are Not tracked and no response will be forthcoming):
You really think Apple is purposely writing code specifically to unmount external storage drives...? And you think they are doing that especially on the 2023 Mac Mini, for some reason?
No. This is a bug.
Update: Later same afternoon, Lexar 128 GB USB flash drive became corrupted. Unable to connect, much less repair, with Disk Utility (permanent beach ball). This same Lexar worked fine many times on my old Mojave system. I did a few tests with smaller, newer 4 GB and 32 GB USB flash drives and had no problems, so I can't rule out that the Lexar went bad. But I see there are other reports of disks being corrupted while attempting to use with Sonoma. So, backup your external media early and often with Sonoma!
External SSD keeps disconnecting after upgrading to Sonoma
