Sequoia update has caused mounting issues with external hard drives. Ex: had one working and then all of a sudden M3 Max MacBook Pro stops recognizing the device. Now, it won't even find it when it's plugged in. Device works fine on other devices.
In my case, since I installed Sequoia, I can hardly ever eject any flash memory. It always tells me that I can't because they are in use by some other program. I have to force eject or shut down the laptop. With every upgrade I see Apple's quality and confidence drop a lot!
Same. But after updating to 15.3 my external hard drives don't show up at all. They will trigger applications, but won't even show in Disk Utilities. The main hard drive won't show there either when an external drive is plugged in. When I disconnect the external drive it gives me an error that the disk "can't be unlocked".
When trying to resuscitate lost drives, I can recommend popular at home rescue programs can be useful to keep the drive mounted while you drag files onto your desktop to retrieve them and/or rescue files. Had less success with bringing drives to 'pro' disk rescue services who were charging well over $1400 to say that once they got to the info on my most important lost drive, that the drive ate itself - and all the info on it. They returned it w/o success or charge along with another drive that I was able to mount on my computer using a full-feature data rescue program. Going forward, make sure to purchase drives with multi-year rescue coverage built in. That has been a good backup while experiencing this problem since 2022.
As for resuscitating drives, my fix has been to run the drive through Check Disk tool on my Windows laptop. Fixes whatever errors are on the drive. Of course this only works on FAT or NTFS, eg ExFat drives, which is what my problem drive is formatted.
I had success ejecting the drive after using AI (Grok) to troubleshoot. Not sure if this is all the issue is but I was able to kill the PID by using terminal commands to get my EHD to eject. This is the process that helped me:
1. Check for Hidden Processes with lsof:
• Open Terminal again.
• Type: sudo lsof | grep /Volumes/DRIVENAME (replace DRIVENAME with the exact name of your external drive as it appears in Finder).
• Enter your admin password when prompted.
• This lists any open files or processes using the drive. If something shows up (e.g., a random app or system process), note the process name or ID (PID), then quit it with sudo kill -9 PID (replace PID with the number).
• Try ejecting again after.
2. Force Unmount:
• If diskutil eject didn’t work earlier, try forcing the unmount:
• In Terminal, type: diskutil unmount force /Volumes/DRIVENAME (again, use the exact drive name).
• This is a stronger nudge than the regular unmount and might override whatever’s locking it.
3. Spotlight or Time Machine Interference:
• If the drive’s being indexed or backed up, macOS can be sneaky about it.
• Disable Spotlight temporarily:
• Go to System Settings > Siri & Spotlight > Spotlight Privacy, drag your external drive into the “Prevent Spotlight from searching” list, and click “Done.” Wait a moment, then try ejecting.
• Check Time Machine:
• System Settings > Time Machine—if it’s mid-backup, pause or skip it, then eject.
After reformatting my two Time Machine externals, both are working now. Strangely, the crashing of my Photos external drive (Mac OS Extended Journaled), which I decided not to reformat, has also stopped.
That said, the Photos external can't be ejected because some "processes are in use" or something to that effect.
But no more kernal panics or constantly crashing apps. I can live with this.
Since your problem is totally different from the Authors you should start your own topic with details of your Mac, system, drive, etc . as described in this Apple document: Writing an Effective Apple Support Communities Question - Apple Community
That will get responses from those who will be more familiar with that problem then those coming here.
AlWeir wrote:
Was reading this morning that HFS+ volumes are not supported in Sequoia.
According to Apple's documentation, Sequoia supports HFS+.
File system formats available in Disk Utility on Mac - Apple Support (CA)
Tinx_Lvs_JC wrote:
Same problem! Since Sequoia, none of my ports/drives work so can't back up, can't use separate mouse/keyboard, can't use Thunderbolt. Did some research and have attempted everything that is within my ability BUT I can't do anything to do with coding. Apple - please fix this bug! It's a crucial issue.
This is a user-to-user forum. Apple does not monitor the community. If you want to make a report contact Apple through this link: Contact Apple Support
I have had a similar issue where my new MBP 16" (m4) running 15.3.1 would appear to randomly lockup. After several instances I tried various things while it was happening. This is what I noticed:
I examined all logs after the system became responsive again and the only thing I could find was in the wifi.log and referenced the keyboard and usb port the keyboard was plugged into.
Wed Feb 19 16:22:00.852 Usb Host Notification hostNotificationUSBDeviceRemoved USB2.0 Hub seqNum 3026 Total 0
Wed Feb 19 16:22:00.857 Usb Host Notification hostNotificationUSBDeviceInserted USB2.0 Hub isApple N seqNum 3026 Total 1
With that in mind, the next time it happened I immediately unplugged the external keyboard and the problem went away almost immediately. Something about that keyboard was causing the MBP to shut down the USB bus it was plugged into. It appears, since I have not looked deeper, that the internal keyboard, trackpad, and wifi are affected when that bus is shut down.
I have swapped out the cable on the keyboard, and ordered a backup/replacement keyboard just in case. Waiting to see if this happens again. This keyboard while less than a month old did work fine with my previous Intel based MBP (late 2019).
My thoughts are that either newer MBPs are more sensitive to USB power issues, or, something has changed in OS X that makes it handle USB power issues differently. I do hope a software update is able to address this. This is also not the first time I have had a Matias keyboard exibit electrical issues, so this may also be my last one from them.
Advice: Try swapping out cables and keep raising this issue. Also take a look at the wifi.log, since it appears to be the only place where USB issues get reported.
-- Frank
Bring up the Info pane for the drive - Control (right) - click and select Get Info. That will tell you what the format is:
If it is an older HFS formatted drive or one formatted in some Linux filesystem (e.g. Btrfs, ext3, ext4) variant, then it won't be recognized by Sequoia.
I've got the same issu with my I Mac and an external HDD. It stopped at 47-48% of the backing or stopped by itself!
Bad news. I'm not able to get a entire Bckup for my puter .
Interesting. I have two SSD's running for backups running with Time Machine and CCC (both are Samsung) and have no problem with either app backing up to them since I upgraded to Sequoia. I don't partition my backup drives.
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!
Hello, I’d just like to confirm the mention of “ext4” not being compatible with Sequoia. Would this be for locally connected drives or all drives i.e NAS? The reason I’m bringing this up is that Synology suggests that “EXT4 is for speed, NTFS for easy compatibility with Windows. Forget about the rest.” I have 16 TB of Synology storage running ext4 connected to my M1 MacBook Pro running Sonoma with no issues. Just looking down before I step in it.
Sequoia 15.0 bugs - external hard drives
