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Monterey struggling with External SSD

I had meant to add this to another tread but can't now find it - not even in Safari History.. Basically since upgrading to Monterey my MacBook Pro can't connect correctly to external SSD.

This is the text I was going to add to other thread.

When I connect my Seagate Fast SSD Media 1Tb which has two partitions one APFS and the other Mac OS Extended Journaled, the OS Ext mounts instantly but the three containers of the APFS take for ever. When I finally managed to open a folder in and APFS container and tried to open it, it threw the Finder into a nervous breakdown which could not be Relaunched via Force Quit. Disconnecting the drive brought Finder back to life. I tried on another port on my MacBook Pro 2016 and tried a different cable but all to no avail.  Connected drive to iMac running Big Sur and all works fine.  I was tempted to reformat the Max OS Ext to APFS but will wait a while and no great urgency. 

Posted on Nov 1, 2021 3:28 PM

Reply
Question marked as Top-ranking reply

Posted on Nov 21, 2021 8:46 AM

KRisseeuw wrote:

1. I had several issues with external USB drives, Disk Utility and Time Machine on a new MacBook Pro M1 Max with Monterey 12.0.1.

USB3-drives are not properly recognized. Time Machine does not work.
2. USB-C drive did not work with either Time Machine or Disk Utility (see below).

Today I purchased a new SanDisk with USB-C connection to make a proper Time Machine backup. The Disk mounted, but Time Machine did not work, nor could I erase the drive with Disk Utility. I tried everything I knew, called Apple Support, but nothing worked (safe mode didn't work).

Workaround: I could solve it by using a Mac Mini 2018 with USB-C-Port, running MacOS Big Sur. Here the external SSD could properly mount and erasing + partitioning worked within 30 seconds. After this treatment, the drive worked well with my new MacBook. Time Machine backups worked fine after that.

Deducting from this, I see that it is not a hardware issue as much as a software issue, affecting both Time Machine and Disk Utility. I am guessing it has to do with MacOS Monterey.

The workaround as highlighted above solved it for the moment.

How on earth is this marked “solved”? The issue — Monterey has hosed compatibility with many, but not all, USB-C external drives — persists, even for KRisseeuw.

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155 replies

Nov 17, 2021 8:09 AM in response to moondav

I am also having this issue on a brand new 14" Macbook Pro running Monterey. At first I thought it was an Apple Silicon compatibility issue, but from the others here it sounds like it is an issue specifically with MacOS 12.0.1. All of these external SSDs worked perfectly with zero issues on my 2015 Macbook Pro i7 running Catalina that I traded in. Now they randomly eject themselves and slow to a crawl, causing my whole system to freeze up. I was about ready to return my new Macbook until I found this thread that seems to confirm that it is a software issue and not hardware. I really hope this is fixed with a software update ASAP.

Nov 21, 2021 5:05 PM in response to ahaynes4

I have the same issue. I have a MacBook Pro and two Mac Minis. After upgrading the MacBook Pro and the Mac Mini I use to run our Zoom Room, I thought I was all set. Then I updated a second Mac Mini that I use as a media server. That one has two external SSDs: 1) Samsung 2TB EVO in an external enclosure, which mounts and works just fine and 2) a Micron 7.68TB SSD I use for video media.


The Samsung works fine. The Micron? Would not mount. So, I moved it to my brand new MacBook Pro (M1) and same result. Shows up in Drive Utility, but won't mount.


I tried erasing and formatting as a new APFS drive, which appeared to work. When I started copy a back-up media set back onto the drive, it disappeared and will no longer mount.


I love Apple... I really do, but every time a major OS upgrade happens, it creates problems with external media. Big Sur's main issue was with my Thunderbolt 3 Drobo. Took Apple a long time to fix that problem.


Oh, well... I guess I just won't use my 7.68TB SSD.

Nov 23, 2021 3:36 AM in response to richard3

I have two Samsung T5 500GB external SSDs connected to a Mac mini (2018) via USB 3.1 (Gen 2).


I've experienced some of the same symptoms especially with regards to mount and unmounting external volumes. It seems that the Time Machine volume, in particular, takes a relatively long time to mount. This may be due to the fact that the Time Machine volume is encrypted. Once mounted the SSD seem to perform normally.


Regarding slow transfer rates, I noticed that some older USB keys (USB 2.0) are ridiculously slow and take a very long time to unmount.


- Pie Lover

Nov 24, 2021 10:56 AM in response to moondav

Okay, further to my earlier post. I have now taken the OWC 480 SSD that I had in a Seagate Backup Plus Portable Drive enclosure and transferred it to another portable drive enclosure. It now works fine on Monterey. I also tried hooking it up to another USB 3.1 controller and a USB 3.0 controller and it worked fine on each of them. So this seems to be an incompatibility with particular drive controllers/chipsets.

Nov 24, 2021 11:41 AM in response to Fool4him

One more thing I forgot to mention. When I put the drive that was in the enclosure I am now using for my OWC 480 SSD into the the Seagate Backup Plus Portable Drive enclosure, it worked under Monterey. This drive, however, is not an SSD. It's a spinning/mechanical drive. So the Seagate enclosure would not work with the SSD on Monterey, but it would work with a spinning drive. Strange, I know. But everything is working now.

Nov 26, 2021 12:38 PM in response to Fool4him

Very helpful... can you provide a link to the external drive enclosure that works with Monterey?


As an update to what I have observed, I re-connected my Micron 7.68 enclosure back to my M1 MacBook Pro, was able to erase and re-format for APFS, and then copy close to 6TB of data over from another source. No disconnects or errors of any kind.


When connected to my (slightly) older Mac Mini (quad core i3), I was able to connect the drive, but could not erase or re-format. After re-formatting on the M1 MB Pro, I would start to copy files and it would disconnect with a few minutes; then, back to unable to erase, et al.


All machines running the current version of Monterey.

Nov 29, 2021 8:59 PM in response to larryg69

iMac 2017 here. Fusion drive 1tb.

install failed on internal drive (hang at first reboot). Forced power off and then it boots but there are issues with reported free space (finder says 76gb, but any attempt of copying files produces disk full error). Tried reindexing and first aid. No chance.


then I tried installing on external ssd connected via usb c.

tried 3 clean installs.

every time it installs, but booting takes 10 minutes (literally). After booted, any disk access (finder, disk utility, etc) essentially hangs for several seconds to minutes.

Dec 1, 2021 6:15 AM in response to Richard Brown4

Ditto, all of the above on an iMac 2017.


I will add: the drive that does not work under Monterey is an SSD ADATA with USB-C connection. I have other (older) drives via USB-A that work fine (seemingly), both HD's and SSD. But the "problematic" drive works perfectly on the same machine if I boot in Big-Sur.


I also tried with a USB-C (on the drive side) to USB-A (on the iMac side) cable and the result is the same. There must be some incompatibility of Monterey with some newer controllers.


Will now downgrade and wait for better times to upgrade...

Dec 1, 2021 4:40 PM in response to Maggot

My respons to mfulat was about slow booting systems, not external SSDs that would not mount which is an entirely different problem.


That being said I don't see any of the usual suspects in your report.


However, here's some food for thought: unless you're using a true VPN tunnel, such as between you and your employer, school or bank's servers, they are useless from a privacy standpoint.  Read these two articles: Public VPN's are anything but private and Former Malware Distributor Kape Technologies Now Owns ExpressVPN, CyberGhost, Private Internet Access, Zenmate, and a Collection of VPN “Review” Websites



Dec 2, 2021 10:57 AM in response to mfulat

I don't see any of the usual suspects in the report. Are you booting from the internal drive or an external SSD? The read and write times are about what I get when booting from an external SSD.


If you have most of your data files on the internal 5400 rpm drive that could be why you're seeing slowing. But boot times are depending on the drive type the system is on.


I would remove all of the items from the System/Users & Groups/Login Items preference pane and see if there's any improvement in performance. If there is then add them back one at a time to see which one slows things down the most.

Dec 4, 2021 3:09 PM in response to mfromwestmount

Same issues here with my 2017 iMac. I have been using a WD 1Tb external SSD connected to the back of the Mac as my boot drive as it is way faster than the built-in drive on the Mac. After “upgrading” to Monterey the drive is there in finder, but the Mac is back to booting off the internal drive. Selecting the external SSD as the boot does nothing. Disk Utility says the drive is locked and times out when trying to unlock it. All worked fine in Big Sur

Monterey struggling with External SSD

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