External Hard Drive Missing After Big Sur Download

I'm not sure First Aid will help. Since you can see it in Disk Utility, in the image below can you select the drive as I have and then tell me the partition information? Since the drive is unmounted I'm not sure if it will show you anything. A drive could go bad in a couple of months but that doesn't usually happen.

Helpfull button won't function in this thread? Why not? Thanks for your post. Sounds incredibly beyond my abilities. BTW just found my old Time Machine. It will not mount. Never even asked to enter a product key. Beyond awful.Ne

thill7 wrote:

Hi Old Toad, thanks for your help!

Format seems to be "Mac OS Extended", here a screen capture:

That drive is being used by Time Machined and should not be used for general storage.

If you need additional general storage then get another external HD and use it. It can also be backed up to TM drive with Time Machine.

Do you have a question in there? We can't help you based on just a rant. We need details of the equipment, system and software used. A good start is to download and run Etrecheck. Etrecheck is a diagnostic tool that was developed by one of the most respected users here in the ASC and recommended by Apple Support  to provide a snapshot of the system and help identify the more obvious culprits that can adversely affect a Mac's performance.

IMPORTANT:

Before running Etrecheck assign Full Disk Access to Etrecheck in the Etrecheck's Privacy preference pane so that it can get additional information from the Console and log files for the report:

Also click and read the About info to further permit full disk access.

Copy the report

and use the Additional Text button to include the report in your reply.

Then we can examine the report and see if we can determine what might be causing the problem.

Hi DeeperDiver, thanks for your help!

Yes, I checked and do have that "External disks" checked. I just posted lengthy reply to another message, with screenshot how it the disk looks on Disk Utility, you can find the picture on that post I think. I understand that erasing/reformatting would probably fix the problem, but I would rather not do it at first option because a) currently I do not have additional external disk where to store the data and b) who's to say it would even help in the long run, as I've read some messages that the problem reoccured after a while.

I keep my rotating EHDs formatted as OS X Extended (journaled). APFS is for SSDs.

If you don't have any files on you're Time Machine that you need you can erase it and start over with a fresh backup. I had to do that a while back as it TM wouldn't get out of the "preparing" phase. An erase fixed it up nicely with no problems since.

cyeoman06, I'm not having the issue, I'm just trying to help. I currently have as WD easystore HD and a Samsung T5 SSD attached to my iMac 2020. I haven't had any issues with either of them. I do have the latest version of the utility software that came with the drives.

What drive are you having issues with? Have you checked with the Drive maker for updated software. Do you see the drive in disk utility when you launch it even if the external drive is not mounted?

Paul

Hey Paul

Many thanks for getting back to me.

Its a Lacie D2 USB3/Thunderbolt 3TB drive. I have just put the serial number in but doesn't appear to be any new firmware updates for it.

Yes I see the drive in disk utility and also when its not mounted, it also shows up on the desktop but not in finder and when I open Lightroom that refuses to see it too. I have yet to try a reformat, do you think it would be worth doing that?

cyeoman -- does the name of your Lacie drive (as it appears on the desktop) have a / character in it? If it does, try taking the / out of the name, then rebooting. (The reboot may be overkill, but it certainly won't hurt!)

Bev, If you launch disk utility and plug in the drive. Do you see the drive in the sidebar? if so can you tell us how it is formatted? APFS, Mac OS Extended, ExFAT, NTFS or something else

I hope this helps.

Paul

I encountered the same issue tonight. MacBook Pro 13" M1 Big Sur v11.0.1, 16gb. Running a project on Premiere Pro. 3 external hard drives (1x WD seagate 4tb and 2x seagate 4tb, all formatted to OS extended journaled) plugged into a U-green USB-C hub. Everything fine in Premier side of things but near the end of the project the WD hard drive starts clicking for no apparent reason. I exported the project during which time there was a few clicks from the WD. On playing the exported video back it had a stutter/skipped second of audio track. I exported it a second time, it had a stutter in the footage near the end. Sent the 2 exported files to my Old Mac (13" MacBook Pro 2011, 16gb, High Sierra. The stutter was still there, so it wasn't an issue with the M1's playback.

Ejected 2 of the EHD's but the WD said it had been disconnected (it hadn't) and was still spinning. Then I got a warning sign saying Mac couldn't repair the disk and to back it up. Finder was showing no EHD's. Disk utility was showing the 2 Seagate. All 3 EHD's were still spinning. I logged out of the M1 and logged back in, it made no difference. I shut down the M1 and all 3 disks stopped spinning eventually. The WD was making click noises like it was breathing it's last.

Started up my old 2011 MacBook Pro, plugged in the WD and it was instantly recognised, no click noises. I'm currently backing up the WD onto another EHD.

It's definately something with Big Sur. I hope there is a fix for this as I'm being forced to complete that project in my 'Old MacBook' which doesn't even have GPU acceleration.

Very interested in the solution to this.

Thanks in advance.

It's a Christmas miracle! I decided to update the driver for my WD My Passport drives while I was at it having updated to Big Sur. Once I did that I restarted and VOILA! My Seagate drive appeared with ALL my files! Maybe it's because I had formatted it as a Mac drive. Who knows, but I am double backing up all those files and I am a VERY HAPPY CAMPER!!!!!

I thought that might be the case. I downliaded the Paragon driver but since I had formatted as Mac extended, it didn’t affect it. On a whim, I thought I’d better update my other WD drives. Hey, when I taught computers, They dodn’t call me GG, the Geek Goddess for nothin’! lol

Same problem. My Mac Pro that was functioning fine with Catalina now will not recognize external hard drives, thumb drives or Kindle. All drives are recognized and functioning on my MacBook Pro which has not been upgraded. Tried all the fixes suggested but no change - Disc Utility does not see anything.

Hellooooo Apple, this seems to be a problem you should be addressing promptly - how can people be operating properly after this upgrade malfunction? External Drives are an everyday item used by nearly every Mac customer on a daily basis.

I can't mount my Seagate external drive right after I upgrade to OS Big Sur, I was try to install the Paragon NTFS for Mac both free version from Seagate site and full version from Paragon are all not working, Other third party NTFS app are even can't install to my any of Mac Pro 2014 and MacBoot Pro 2018 or iMac Pro.

The WD external drives are formatted by ExFat so it's all working very well, Only NTFS drive can't work. Wish Apple or any can find the solutions to solve this problem!