Sequoia 15.0 bugs - external hard drives

Follow-up. Apple was able to help me re-format the SanDisk, which after doing so, the SanDisk did appear on my desktop. We then chose the SanDisk to use for Time Machine auto backups, and this time, Apple had me TURN OFF the "encryption" choice at the time of setting the external up to use for Time Machine.

The external drive has been working for 24 hours, and Apple will follow-up with me tomorrow and then again at a later date.

SanDisk technical support had also suggested it was an encryption error that Apple would need to be notified. All good today! It was ironic that my previous external failed, and the new one failed in the same week but so far so good.

FINALLY FIXED THIS PAIN IN THE *%$£$*

Heres how:

Update to sequoia 15.3.1

Then reset SMC.

Resetting SMC (System Management

Controller)

The SMC controls low-level hardware functions, including:

• Power management (battery issues, random shutdowns)
• Sleep/wake behavior
• Fan speed and thermal management
• LED indicators and display backlight
• External device detection (including SSDs)

How to Reset SMC

For Macs with Apple Silicon (M1/M2/M3)

• Just shut down your Mac and wait 30 seconds before turning it back on.
• SMC resets automatically on startup.

For Intel-based Macs

1. Shut down your Mac.
2. Press and hold Shift + Control + Option +
3. Power button for 10 seconds.
4. Release all keys and turn your Mac back on.

Then Reset NVRAM

Resetting NVRAM (Non-Volatile RAM)

NVRAM stores small but crucial system settings like:

• Startup disk selection
• Sound volume
• Display resolution
• Time zone settings
• Kernel panic logs (sometimes causing crashes)

How to Reset NVRAM

1. Shut down your Mac.
2. Turn it on and immediately press and hold
3. Option + Command + P + R.
4. Keep holding the keys for about 20 seconds.
5. Your Mac will restart, and NVRAM will be reset.

I use Logic Pro and use an SSD and run my projects from it. Every day since updating to sequoia it would eject itself at random times, Logic would crash. Then when I did want to eject my drive it wouldn't do it. Was driving me CRAZY. Hope this helps some of you!

R

This is a USB3 power problem and it's been in Mac OS since Sonoma. I have an M1 MBP and I normally keep an external LaCie dive plugged in to a studio display. Occasionally I take the MacBook on photoshoots and tether to it while simultaneously writing the shots to an external LaCie HDD. Before Sonoma, I never had any problems. After I upgraded to Sonoma the HDD stopped working when plugged directly into the laptop. I took the MacBook and drive to a remote location and suddenly the disk kept randomly disconnecting and disappeared from disk utility when plugged directly into the MBP. When I plugged it into an older MacBook Air with Monterey on it the drive worked perfectly. I connected it the drive to the MBP using a powered USB hub and again, no problems. Sonoma completely screwed up USB power and it sounds like Apple haven't fixed it in Sequoia which is really poor considering there are thousands of reports of this problem. The disk format is irrelevant. Same problems with ExFAT, APFS, MacOS Extended. The only sure fix is to plug the drive in via a powered monitor or USB hub. Just don't get stuck on a photoshoot on a scottish mountain with no mains power and no way of backing up your shots.

I had the same issue with older USB-A spinning standalone hard drives (SSD hard drive and plugged in/powered USB drive both worked).

What ended up working for me was to go to System Settings > Privacy and Security and then "Allow Accessories to Connect" where I changed it to "Always". The drives then showed up. Perhaps something with the USB accessories security setting that was shutting down USB power?

Yes! I can verify that this IS a USB problem. Ever since I purchased a new external drive that has a USB hub and interfaces with my new MacbookPro M3 via USB 3.2 I have had issues with the drive not mounting. The drive mounts fine to my older MacbookPro with Intel chip. This is a 2-bay OWC expansion drive with an external power supply. Brand new. And again, it works/worked fine with the older, Intel-based MacbookPro.

In an effort to solve the problem, I upgraded the new MacbookPro to the latest version of Sonoma (it was running Sonoma, as was my Intel MacbookPro) and that seemed to solve the problem...the drive mounted. ONLY THIS LASTED JUST 3 DAYS and then it stopped again.

To make a long story short, I tried all of the safe boot, etc. suggestions and nothing worked. I ultimately (today) upgraded to Sequoia 15.3 figuring that if I took the machine into Apple, they'd demand that anyway. Still no go UNTIL I read this thread, and decided to try connecting the external drive to the MacbookPro via an old USB C to USB 3.0 cable plugged into a dongle that was then connected to the M3 Macbookpro...and IT WORKED. Drives mounted right up and a TimeMachine backup is running. System Info tells me that it believes that I have a USB 2.1 Hub Installed. (see image)

It of course remains to be seen if this continues to work (recall that I did have it working for a few days on Sonoma until it stopped...that was with a USB C 3.2 connection on the drive to USB C on the M3 Macbookpro connection). But there definitely seems to be something going on with this machine and its USB ports (yes, I tried all 3 ports earlier before the current "fix" and none of them allowed the drive to mount).

Downgrading to a USB 2.1 (or presumably older?) connection seems to work. FWIW.

Yes, it was not the fix. I’ve only had issues with large (5TB) portable drives, Seagate and WD connected via a powered USB hub. Occasionally, the drive disappears especially after a reboot or startup if my Mac Mini M4 Pro has been shut down for some reason. After trialling the SMC and NVRAM fix, the external drive just didn’t show up as connected. My only way to get the drive to reconnect has been to plug the drive into my old 2014 Asus Windows Laptop running W10 and running the Check Disk tool. It always shows there are errors but fixes them and then when I replug back into my Mac Mini, it shows straight away.

Like many, I had this problem - my particular set up is as follows -

External Drive : OWC Aura P12 Pro PCIe 3.0 NVMe M.2 2280 SSD with 2x 4TB ram cards

Mac : Mac Studio M1 Ultra

OS : Sequoia 15.3.2

Had a Bad Idea and decided to clean up the major mess behind the big screen of tangled cables, USB hubs, power supplies, external drives, a mini Tardis machine etc etc - your basic horror show from plugging in every next device in, without ever rationalising any of it.

The OWC SSD had worked flawlessly since installation in June '23 - and just used any old generic thunderbolt cable to connect it and all worked fine.

After untangling and losing a *LOT* of excess and not often used gear, everything booted back up fine -

Until the Sequoia update ...

The OWC no longer appeared in either Finder or Disc Utility, which was weird because it had been a rock solid always there device for 1.5 years. Because there were no directories or files visible from the OWC could not use for backup or as an extension for big apps of the Mac's 1TB hard drive - a big drama!

For the same reason could not use the right click trick on any OWC files or folders in Finder, followed by Get Info / Sharing Permissions to alter the Permissions for the OWC.

Strange how often the basic 101 support solutions sometime work?

Changed the Thunderbolt cable between the Mac and the OWC to a "genuine" Apple Thunderbolt white job (not sure what it came with) and hey presto OWC + all folders and files appeared in both Finder and Disk Utility.

Apple are (inconsistently) picky about what, and for how long, 3rd party devices can be used with their gear, despite not making a whole bunch of external devices they know you will need over time (and they often sell those third party devices in their stores).

Morals -

1. 1. 1. Keep a set of genuine apple cables around to test when you have a non connect issue (I know that 3rd party ones are often better made, cheaper and in more convenient lengths)
      2. Before upgrading any OS on any device, wait and search known issues before upgrading, especially compatibility and support issues.

Just feel a bit silly reporting such a simple fix .... cheers Max

I'm having a similar experience..

I use an OWC Thunderblade external 4 x SSD unit connected by Thunderbolt to a Mac Studio running Sequoia 15.7. It's formatted using Disk Utility as a single volume RAID 0, Mac OS Extended Journaled.

The volume spontaneously unmounts a minute or two after restarting the computer. A 'disk (name) not ejected properly..' message then appears.

Eventually, I discovered that after excluding the volume from Spotlight indexing, the problem was 100% eliminated. In my testing, I found the behavior to be repeatable every time.

For me, this is a new issue after upgrading to Sequoia. I ran this same setup with Ventura with 0 issues.

Interestly, (and thankfully) this behavior does not occur with my 2 other TB-attached external drive units, a SATA hot-swap box (Mac OS Extended Journaled) and a small SSD unit (APFS). All of those drives are a single volume per drive formatted.

I found this thread when my new M4 Macbook Pro would not recognize an external SSD. Works fine on Ventura on another Macbook Pro. Did not show up on Sequoia 15.1, nor did it show up in Disk Utility. This was the change that fixed it. Changed to Always and immediately it showed up. Plus 1000 for this tip. Thanks!

Edit: I replied to AlWeir who suggested in Settings: Privacy and Security > Allow Accessories to Connect. That was the tip that fixed it. Thanks!

TLDR; Try a new micro-B USB cable. Seriously, that fixed it for me...

Got a brand new mac mini M4 pro delivered yesterday. Backed up to my time machine on my old iMac. Tried using that in migration assistant on the new mac mini... hmm, that's odd it's not finding the drive when plugged into an apple adapter. Just migrated via wi-fi instead. Plugged the time machine drive back into the old iMac and it was also not mounting. Hmm, I guess it could have gone bad but the timing is very suspect. Plugged it into a PC to check whether the drive was cooked and it was mounting and formatting fine. As a last resort, tried another cable I had laying around and it mounted instantly. It seems to only be an issue with micro-B USB cables, at least anecdotally. If your drive is using micro-B, try or buy another cable and hopefully it fixes your issues. Cheers

I want to add my voice to this.

Since updating to Sequoia in November, 2024, neither of my external USB-C drives have functioned normally: spontaneously unmounting; Photos (my library lives on an external drive) having to quit, rebuild or restore from iCloud; Time Machine backups via USB-C taking FOUR HOURS to complete, even when no files have been changed or added.

But the kicker is that since these problems began in December I've had EIGHT kernal panics, including three in the last 24 hours. I thought it might be an incompatability issue with the external drives' HFS+ journaled extended file systems vs. APFS, so I chucked five years of Time Machine backups, and erased and reformattted the Time Machine drive to to APFS—and halfway through the first backup the process simply quit, and then crashed my iMac simultaneously, too.

I've run Diagnositcs ("No issues found"), and started up in Safe mode. I've reset the SMC and zapped the PRAM. I ran EtreCheck, and it was clean. The only thing I can think of is that something is causing the OS to not play properly with USB-C. (FYI, the drives are both G Tech G-Drive mobile, 2TB and 4TB.) I've unmounted and put both drives aside to see if the panics continue.

I'm currently backing up—flawlessly—to an ancient Seagate USB 2.0 drive. I can't be sure, of course, but it seems that USB-C is the culprit.

iMac, late 2020 (last Intel model)

Sequoia 15.2

32G RAM

What I have been doing since this issue is:

1. Plug the hard drive into an older mac I have (with Mojave in my case)
2. Open terminal and run sudo pkill -f fsck
3. Once the disk boots I run first aid in Disk Utility
4. Then if I eject and plug onto the Sequoia, it boots as normal

Annoying but that's what's been my resolution so far until Apple does the right thing.

Can Disk Utility find it?

Privacy & Security>Allow Accessories To Connect

A work around: Select Finder: GO: Computer:

You should see the mounted external drives which you can then use in the normal manner.

Its a Bug in OS 15.2 that doesn't allow this to show up in the finder side bar nor in the desktop even when these defaults are selected in the Finder Sidebar settings.

Maggot wrote:

I want to add my voice to this.

Since updating to Sequoia in November, 2024, neither of my external USB-C drives have functioned normally: spontaneously unmounting; Photos (my library lives on an external drive) having to quit, rebuild or restore from iCloud; Time Machine backups via USB-C taking FOUR HOURS to complete, even when no files have been changed or added.

But the kicker is that since these problems began in December I've had EIGHT kernal panics, including three in the last 24 hours. I thought it might be an incompatability issue with the external drives' HFS+ journaled extended file systems vs. APFS, so I chucked five years of Time Machine backups, and erased and reformattted the Time Machine drive to to APFS—and halfway through the first backup the process simply quit, and then crashed my iMac simultaneously, too.

I've run Diagnositcs ("No issues found"), and started up in Safe mode. I've reset the SMC and zapped the PRAM. I ran EtreCheck, and it was clean. The only thing I can think of is that something is causing the OS to not play properly with USB-C. (FYI, the drives are both G Tech G-Drive mobile, 2TB and 4TB.) I've unmounted and put both drives aside to see if the panics continue.

I'm currently backing up—flawlessly—to an ancient Seagate USB 2.0 drive. I can't be sure, of course, but it seems that USB-C is the culprit.

iMac, late 2020 (last Intel model)

Sequoia 15.2

32G RAM

Update #2:

My iMac hasn't had a kernal panic since I disconnected the two G Drive mobile externals. Prior to disconnecting them, on January 10th, I had three panics in one day. So something's definitely amiss there. But glad that the panics have stopped.

I installed 15.3 yesterday, hoping it may solve my issues. I connected the G Drive with Photos on it, but this time using the (included, OEM) USB-A to USB-C cable. Everything worked fine until about an hour in, when I noticed a bit of lag when scrolling through photos. After leaving the iMac for about an hour, I got s familiar message: "Photos has to quit" or something to that effect. I disconnected.

I told the senior Apple support person that I'd wait until 15.3 to try anythoing further, so I guess it's time to get on that merry go 'round again. Frankly, I'm thinking this will be a complete waste of my time. I think they've somehow broken the USB-C implementation at the OS level, and since it manifests differently across machines, but not globally, they're not all that concerned about fixing it.

We'll see. The alternative: both my USB-C drives somehow simultaneously reacted to the install in a bizarre manner. Seems a stretch.