With Monterey update, can't see certain hard drives

External HDs were not able to connect to my iMac until I unplugged my Wacom Tablet. Now they are mounted. Took me days of researching this issue until I read this solution in this forum.

Can’t understand why this solved my problem, but my issue has been resolved!

Vettmanz06

So after weeks of not being able to access my sample library and music files on my external drive post-Monterey update, I was feeling very discouraged, especially after searching this forum and the web to no avail for a solution to the indexing and spotlight issue with the current OS. Today I am pleased to say I have found a solution that works and I am currently watching the light on my Glyph studio raid flicker as Spotlight scours the files on said HD.

First, go into Finder and press Shift+ Command + . (yes that is a period)

This will allow you to see the hidden files on your external drive

Search for a file named like the one below

.metadata_never_index_unless_rootfs

delete the file in Finder, then eject the drive. Then re-mount the drive and run this in Terminal:

sudo mdutil -a -i on

Once that is done your external drive should begin indexing and you should be able to use spotlight to locate files on your ext HD.

I have a 2015 iMac. upgraded from Mojave to Catalina. My 10T G-drive would not show up after the update. I wanted to rule out the cables so I took the "Apple" Thunderbolt cable (Male on both ends) and the "Apple" adapter cable female Thunderbolt to USB-C to the Apple store. They checked the cables and the cable were working perfectly. 3 days later after exhausting everything and pulling out my hair, I bought a Belkin USB-A to USB-C cable (plugged the it into the non-Thunderbolt USB-C port on the G-drive and voila the drive now shows up on my iMac. There is something about the update that renders the Thunderbolt option unusable. I thought the hard drive was toast but it was only a stupid cable glitch. Apple should be looking at this problem and letting people know. So glad I didn't end up spending money on data recovery.

For some reason, the bug appeared again this morning when it stopped without me doing anything for 15 days.

On my late 2015 iMac, the bug is also accompanied by several symptoms: Extremely long boot time, Bluetooth disabled at startup and impossible to re-enable, partial mouse operation (touch does not work, but pointer and clicks work ), impossible to mount the samba network disks, while the NFS are well mounted... After a while, the Bluetooth reactivates and these symptoms disappear, on the other hand the USB hard disks remain invisible and inaccessible.

Oh my gosh! 4 days, 2 days on with Apple support and this is the answer! I unplugged Wacom and restarted Mac…Bluetooth worked and my external hard drives mounted. Then I could plug Wacom back in and it worked. Somehow flag viathelens post so it shows up in searches sooner!

Really unbelievable 😵‍💫

My SSD hard drive and the cable worked for 2 years... and after the update to macOS Monterey, I could not use Time Machine anymore, it stopped the backup after a short moment. I tried to format the disk... and than could not see it anymore, it did get mounted. I formated on a old MacBook and finally found the above suggestion to use an Apple cable, after what every thing worked as before!

The length of this thread and the variety of suggested solutions reveals major issues with Monterey 12.3.

Is the problem caused by Apple’s OS update or by the manufacturers of external drives? If you believe the latter, apparently WD (Western Digital) has been working on a fix at their end - or so I read in this discussion. My LaCie Drive (RAID) was one of my drives that was affected. It mounted, but Adobe files would not open, nor would files for some other applications (Digital Performer). LaCie uses, among others, Western Digital hardware in their drives so maybe that is the issue.

My SOLUTION (sort of) was to downgrade to Big Sur on my laptop. In my case, this was NOT EASY and took a lot of time on calls to Apple Senior Tech advisors to figure a way to do this safely. One wonders why Apple does not provide the option to downgrade to Monterey 12.1 (which was working trouble free). THAT would been the best solution in my case. But Monterey 12.1 disappeared completely from Apple’s servers after the update to 12.3.

Does anyone know if the Monterey 12.3.1 solves these issues? I would like to move back up at some point but won’t until I know the OS is stable.

I recently upgraded my Monterey to 12.3.1.

Immediately out of my three external hard drives, one of them can't be recognised any more.

After spending hours with the Apple support team on the phone, there is no quick solution apart from trying my hard drive on other people's Mac.

Lucky I found this forum here after the phone call.

By switching the USB3.0 USB-B to USB-A cable to an old USB2.0 USB-B to USB-A one, the hard drive came back to life.

Even thought the speed is unbearable with USB2.0 (as that is the spare one I have at the moment.) but I am happy for knowing there is nothing wrong with the hard drive and my files are safe. I will now need to rush to get a new USB3.0 USB-B to USB-C cable and hope it can work with the current OS. I also tested my current USB3.0 cable on other PC and there is nothing wrong with it.

I am surprised the Apple support team didn't mention anything about the OS upgrading issue has caused it.

Just got 2022 14 macbook pro , it seem cannot detect Mybook WD harddrive external with exfat format.

the HD works with my old macbook pro with mac BigSur. can anyone help ?

i tried everything changing the cable etc. nothing works, it seem missing exfat driver for my external HD.

any solutions ?

I had the same problem with an older hard drive (LG). It was recognized by another macbook with older OS. On Monterrey i tried using a usbc-usb adapter (apple) and it didnt work. But it worked like a charm with a generic adapter QacQoc (those multi port adapters).

Here I posted a temporary solution...

https://discussions.apple.com/thread/253300041?answerId=256243870022#256243870022

Here you have a temporary solution till Apple update Monterey and solve the bug!

https://discussions.apple.com/thread/253300041?login=true&page=1

That corresponds with the WD statement given a few posts above yours:

https://discussions.apple.com/thread/253298287?answerId=256481777022#256481777022