None of these helps. It's a problem inherent to Monterey, through 12.5.1.
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External drives keep dismounting
- Thread starter JW5566
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I have this problem on a 2018-style Mac Mini (Intel) and a MacBook Air M2, both running Monterey. Never had the problem on the Mini up through Catalina, but then I 'upgraded' to Monterey. The MB Air arrived with Monterey installed.
I've tried everything mentioned by prior posters and more, no change. This keeps me from using the Mini as my network backup host, which worked well until Monterey.
I just don't get Apple lately. So many reliability regressions.
Following this thread with great interest. I'm not a tech guy; I'm just a long time Mac user. I'm not certain this problem is confined to Monterey.
I've got a 2018-ish MacBook Air, which is still running Mojave. Last month, one of my external hard drives wouldn't mount on it; it showed up (greyed out) in Disk Utility, but I couldn't run Disk First Aid on it. Tried everything - new cable, restarting, different ports, even a different (and older) MacBook. Two days later, nothing could make it mount. Thought I'd have to go to a data recovery place, but figured I'd try Disk Drill first, which had been recommended to me. (It's not supposed to fix a damaged drive; it's supposed to help recover data.) With the free version, I could see that all the files were still there, so I bought the full version, and started the recovery. Out of the blue, the drive appeared again, mounted on the Air. Drive has been fine ever since.
Cut to last week. I bought a new Mac Mini (M1) which, of course, runs Monterey 12.5.1.
Same thing happens with a brand new external drive from Seagate. Wouldn't mount on the new Mini, or the Air running Mojave.
Ran it through Disk Drill, and it mounted after several minutes.
No idea if using Disk Drill actually did the trick, or if it was just a coincidence.
Gotta say, this problem makes me really skittish.
I've got a 2018-ish MacBook Air, which is still running Mojave. Last month, one of my external hard drives wouldn't mount on it; it showed up (greyed out) in Disk Utility, but I couldn't run Disk First Aid on it. Tried everything - new cable, restarting, different ports, even a different (and older) MacBook. Two days later, nothing could make it mount. Thought I'd have to go to a data recovery place, but figured I'd try Disk Drill first, which had been recommended to me. (It's not supposed to fix a damaged drive; it's supposed to help recover data.) With the free version, I could see that all the files were still there, so I bought the full version, and started the recovery. Out of the blue, the drive appeared again, mounted on the Air. Drive has been fine ever since.
Cut to last week. I bought a new Mac Mini (M1) which, of course, runs Monterey 12.5.1.
Same thing happens with a brand new external drive from Seagate. Wouldn't mount on the new Mini, or the Air running Mojave.
Ran it through Disk Drill, and it mounted after several minutes.
No idea if using Disk Drill actually did the trick, or if it was just a coincidence.
Gotta say, this problem makes me really skittish.
I found that the following (temporary) solution works to mount the unmounted disks. I noticed that after First Aid is complete, the disk will be put in read only mode; a restart solves this.
Open Terminal
sudo pkill -f fsck
Anyways, if your disk happens to be ExFAT, and you remember improperly removing the disk the last time you used it, chances are, fsck is holding it hostage (metaphorically, of course). fsck is trying to repair the disk, but it will stall forever, so you want to launch Disk Utility, and the Terminal. Try to mount the disk, and switch to Terminal and write sudo pkill -f fsck. The disk will mount in read-only mode, and from there, you can repair it with First Aid in Disk Utility. This won't work for non-ExFat drives, as macOS manages them differently.
Open Terminal
sudo pkill -f fsck
Anyways, if your disk happens to be ExFAT, and you remember improperly removing the disk the last time you used it, chances are, fsck is holding it hostage (metaphorically, of course). fsck is trying to repair the disk, but it will stall forever, so you want to launch Disk Utility, and the Terminal. Try to mount the disk, and switch to Terminal and write sudo pkill -f fsck. The disk will mount in read-only mode, and from there, you can repair it with First Aid in Disk Utility. This won't work for non-ExFat drives, as macOS manages them differently.
I've been following this thread for a few weeks as I've had the same disconnecting drives issue. I just upgraded to Ventura and am still having the same problem. Has the update fixed it for anyone else?
My drives won't disconnect if I use either of the following hubs:
https://www.amazon.ca/Wavlink-Docking-Station-Charging-Ethernet/dp/B09X1GQFW2/ref=sr_1_6?keywords=wavlink+13+in+1&qid=1666642874&qu=eyJxc2MiOiIxLjM0IiwicXNhIjoiMC44MSIsInFzcCI6IjAuOTIifQ==&sr=8-6
ca.targus.com
They do disconnect if I use either of these:
www.startech.com
My drives won't disconnect if I use either of the following hubs:
https://www.amazon.ca/Wavlink-Docking-Station-Charging-Ethernet/dp/B09X1GQFW2/ref=sr_1_6?keywords=wavlink+13+in+1&qid=1666642874&qu=eyJxc2MiOiIxLjM0IiwicXNhIjoiMC44MSIsInFzcCI6IjAuOTIifQ==&sr=8-6
HDMI and DisplayPort Docking Station with Power | Order at Targus
Streamline your workstation with this USB-C HDMI and DisplayPort docking station with 100W power. Explore a Docking station that supports USB 3.0 and video.
They do disconnect if I use either of these:
1.6ft (50cm) USB-C to Micro USB-B Cable, USB 10Gbps, Data Cord, 3A, USB C to Micro-B Data Transfer C
Connect USB Micro-B devices to your USB Type-C host with reduced clutter
www.startech.com
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Been running my Mac Studio M1 Max for a few weeks now. I have six 3.5" HDs in three or four different kinds of housings (three on all the time) and three SATA SSDs connected via USB adapter cables. There's one powered hub and one unpowered. I will wean myself off this confusion in time.
I haven't had a dismount yet.
I keep the spinners going with Amphetamine as it's pretty bad when they spin down. I don't allow the Mac to sleep although my two monitors do.
I haven't had a dismount yet.
I keep the spinners going with Amphetamine as it's pretty bad when they spin down. I don't allow the Mac to sleep although my two monitors do.
I'm having this problem on my Mac Studio running Monterey. Does anyone know if it has resolved with Ventura? I never had this problem with my older iMac. Same drives, except I got a new SSD external and it also ejects. Basically, all my various drives get ejected at one time or another so it is not the drive or a cable or it would be isolated to one of the drives.
I haven't had it happen yet, but I figure it's too soon to say, and I take extra precautions. It most commonly has been happening for me with my Time Machine Drive. So, for fear of having a corrupted backup, I monitor a backup closely. First, I go into settings and make sure the hard drive is not going to go to sleep on my 2020 Intel MacBook Air running Ventura. Then I keep using the computer while the backup to the external WD drive is happening. I don't leave it connected and make sure to do the next backup before so much has changed that the backup will take a long time.
I have had it happen also when transferring large files to external drives.
This information might not be very helpful, but since no one else has responded and it is still early days for Ventura, I thought I'd give some feedback FWIW.
I have several external USB drives and would like to leave them connected all the time, as I often did with my MacBook Pro, which I never updated to Catalina (the last macOS it could handle).
I have had it happen also when transferring large files to external drives.
This information might not be very helpful, but since no one else has responded and it is still early days for Ventura, I thought I'd give some feedback FWIW.
I have several external USB drives and would like to leave them connected all the time, as I often did with my MacBook Pro, which I never updated to Catalina (the last macOS it could handle).
This is happening to me on multiple WD and Seagate drives. It worked just fine before the update. I don't know what to do and I have a lot of work that I need to access but it keeps randomly ejecting the HDs.
When I was having this problem, I suspected it was a bad hub, but when I got a new mac the problem went away. I also discovered that "Put hard disks to sleep when possible" results in a big performance hit.
I have a repurposed 512GB SSD from a 2013 Mac Pro in an OWC case designed to work with Apple's incompatible sort of M.2 devices. It worked fine with the upgraded Mac Pro but was consistently unmounting under Monterey. With Ventura it seems to be fixed. I copied about 50 GB of data and left the drive mounted all weekend and it worked without any issues.
Edit: This is on an M2 MacBook Air.
Edit: This is on an M2 MacBook Air.
Following.
I hoped the problem was with my old computer I was replacing, but now it’s occurring on my brand new MBP. I was going to start trying different cables and whatnot, but it sounds like it’s a software issue.
I hoped the problem was with my old computer I was replacing, but now it’s occurring on my brand new MBP. I was going to start trying different cables and whatnot, but it sounds like it’s a software issue.
For what it's worth, my problem appears to be solved.
Ventura 13.0 and I unchecked > Settings > Battery > Options > Put hard disks to sleep when possible
Ventura 13.0 and I unchecked > Settings > Battery > Options > Put hard disks to sleep when possible
"For what it's worth, my problem appears to be solved.
Ventura 13.0 and I unchecked > Settings > Battery > Options > Put hard disks to sleep when possible"
Thanks - now trying this through energy saver on my M1 in Ventura.
Ventura 13.0 and I unchecked > Settings > Battery > Options > Put hard disks to sleep when possible"
Thanks - now trying this through energy saver on my M1 in Ventura.
I am not even the one who has to go through this and I feel like crying.@WinterWolf90 I updated today actually on this thread:
Does Monterey Have a Bug with Mounting External Drives & Images?
An update on my earlier posts about two WD 2TB drives that stopped working after I upgraded my 2020 Intel MacBook Air to Monterey (random dismounts). To recap, both drives were working fine before upgrading and both still worked fine on an older MacBook Pro on Catalina, potentially ruling out...forums.macrumors.com
They're working fine again now on Big Sur. It was a painful downgrade as I had to factory reset then update from Catalina to Big Sur. It took ages and I had to install all my apps again. However I rely on external drives for work, so I had no choice. I'll remain on Big Sur now.
If it is a timeout problem Amphetamine should fix it. The app, not the drug.
But from reading this thread I am not sure that's it though. Maybe report back after a while.
I'm running an M1_Ultra max memory etc. My old Mac Pro trash can running Monterey started dismounting the drives. It's no better on M1 box even with ventura. I did what everyone else did; new cables new drives etc. had ZERO effect on the prob. The drives do show back up after a reboot for a random amount of time. Apple has really gone downhill on their coding... even the IOS 16 stuff is having issues on my phone & iPads. But on the plus side home kit seems to be working better now.
Same for me. I've had USB drives dismounting since my Power Mac G3 days and it still happens to me today on my Mac Studio.
I am running MacBook Pro with M1 Max and the same issues. Cannot say that HomeKit is any better based on my experience.
I was really getting frustrated with it and looking all sorts of Google results up. In the process I may have found something given that the one USB stick (was happening with another one too and both being tried through multiple converts to USB-C and hubs with constant disconnect issues) that I was having the most issues with now appears to be settled down. WhatI did that appears to have solved the problem (fingers crossed) was:
System Setting -> Displays -> Advanced and then turned off "Prevent automatic sleeping on power adapter when the display is off". Even though I was at the keyboard and therefore the display had no reason to sleep, this may have something to do with it. I can only say that because it is the only thing I have changed in my setup.
UPDATE: Left the computer to complete the transfer and it appears that when the screen went to sleep it caused a problem with the copy. I have unplugged the external monitor (that is connected via USB-C cable) and will try again.
UPDATE 2: Back to failures. Unplugging the monitor did nothing, though I did not reboot afterwards. Ug!
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sorry for the delay - I believe it did, but the whole system has been off for a little while.