External Hard Drive Missing After Big Sur Download

Did you format the Seagate for Mac? Try downloading the latest WD driver. Once I did that, my Seagate showed up. The NTFS did nothing. My WD drives had been showing up but I updated the driver to tge latest for Big Sur. Everything is working fine now.

All My Seagate external drives are fully loaded, If I format it now, I'll lost all the data store in the drives, I had more than 30 Seagate external drives in hand, If Mac OS No longer to support NTSF format, I'll stop buying Seagate external drive and switch to WD or other ExFat format drive, But can't do any thing to my old NTSF drives!

Clarification: I meant originally when you first used it, not reformatting it now.

Try installing the latest driver for WD for Big Sur.. That’s what worked for me when the latest NTSF driver didn’t work. I’d basically given up and it appeared!

Paragon systems also has a 3rd party NTFS driver. I haven't tested it as I format my drives Mac OS extended when I purchase them. After copying the included software to another drive.

I'm wondering if Big Sur doesn't support NTFS out of the box anymore. Hopefully this will change.

Paul

Same issue here on my Mac Mini (2018). Updated to Big Sur 11.1 and now my 5TB external drive (connected via USB C) will not mount. First Aid has no impact, and going to Disk Utility -> Mount does nothing, I can just keep clicking it without any impact. It is formatted as APFS (Encrypted). I even tried removing the password from Keychain and manually re-entering when trying to mount (prompt came up correctly), but never mounts. Worked without issue before updating to Big Sur, and other smaller drives continue to work without issue.

iBoysoft NFTS software and NTFS for Mac from Paragon (or From Seagate) are all useless for me, iBoysoft NFTS software can't even finish the install , I believe is Big Sur stop all NTFS drives mount on desktop, wishing Apple can do something at next Big Sur version upgrade!

I found that the iBoysoft is not allowing everything to be read - still missing files (not showing up) off external. I have decided to take stuff of hard drive, reformat and put back on. Pain in the ----- ! I really need to be able to move between Apple and windows - why do they want it to be so difficult for us?

Hi,

If your mac produced after 2017, T2 chip cause these kind of problems. I have been dealing different type issue which is related with the T2 chip since last week.

And last version of Big Sur 11.1 destroyed my MBP 2019 ...

Same problem for me. Impossible to see my external disks anymore. I am just upset and exhausted about all the border effects i get on my new Mac Book since i upgraded to Big Sur. I purchased for more 4000 euros a few weeks ago. This upgrade is really an amateur job.

Yes I agree, this is really amateur. You can disable T2 chip.

1- restart your mac

2- push down command+R

it will login to recovery mode. Top of the window you will ser the Utilities option, click startup security, in the next window click no security and allow booting.(to be helpfull not read all the discussion here maybe you have done it)

But the real problem is for the machintosh computers are when you update it, it also updates BIOS(different name in macs not BIOS). So that is the problem. It destroy’s firmware.

After the last update it burned my USB hub. And usbc ports stop working. Not able to charge it. Now my mac is getting “fixed” in apple service...

Windows is really shity OS but it does not touch BIOS.

Thanks! My old 2013 laptop had/has no problem reading and writing to my externals. It is the brand new 2020 MacBook pro that comes loaded with Big Sur that has the issue. I'm waiting impatiently for the 3rd party companies to update their software to read NTFS files.

I got the new 2020 MacBook Pro M1 13" and connected an external HGST hard drive formatted by a PC to ExFAT. It was seen but could not be mounted. What solution is needed for Big Sur to be able to read and write files on that external HD?

Apple Support had me reset System Management Control (SMC) and reboot, but this did not solve the problem.

The problem happened regardless of whether the drive was connected on its own via a Sabrent USB connector directly to the MacBook's USB port (with a C-to-A adaptor) or whether the drive was in a 2-bay Innatek dock connected via USB-A to a CalDigit TS3 multi-port dock that's connected via Thunderbolt 3 cable to the MacBook. The error showed up in a pop-up message from the Mac's Disk Utility app that said "Could not mount “{disk name}”. (com.apple.DiskManagement.disenter error 49223.)"

Apple tech support is looking into it. But if you have wisdom on this problem, I'm interested in what has worked for people with this problem (an external hard drive formatted by a PC as ExFAT is not openable).

Thanks!

No use, Even I purchased the Newest version for OS Big Sur still can't mount NTFS external drive from Seagate, Don't waste your money! If you own a new Mac come with the SMC may have the chance to make it work!

Hi there,

yes, i had this issue too and after fiddling around with diskutil in the terminal and what not, this was the solution for me: https://apple.stackexchange.com/a/222950/402233

Just go to Folder /Volumes and there you should find the drive. Then you can drag it to the sidebar in Finder. It doesn't disappear though when unmounted but hey.. at least it's there when mounted :D

Hope that helps.

i am facing the same issue on my mac book air (2017) edition , i have a 1.5tb WD hardisk and it works so slow after i installed Big sur , the partitions on my disk loads after 15 minutes and the data transfer and accessibility is also very slow , i tried the same hardisk on my windows laptop and it works flawlessly . if you do find a solution pls share it here