External Hard Drive Missing After Big Sur Download

I just re-activated my Paragon App and it started working! Now reading and writing to Toshiba external that is formatted for NTFS! Merry Christmas to me!!

Disconnect your hard drive ASAP. Mine got ruined.

Access the drive from WD Utilities app.

Killing "fsck_hfs" seemed to have done it for me.

Thanks for this post, it is what lead me there eventually!

For google:

External hard drive disappeared after upgrade to Big Sur

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

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

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?

Irene806, First launch disk utility and does it show up in the list of drives?

Also is it possible to plug in an external power brick to LaCie drive? Do you know how the drive is formatted? ExFAT, NTFS, HFS+, or APFS?

Let us know and we can help you solve your problem.

Paul

Hi, I just wanted to document my current status with the external hard drive issue.

I had four EHD and lost two of them at the Big Sur 11.1 update.

A 1TB Seagate Back Up Plus for Mac and a 1TB Seagate Expansion Portable Drive continue to work.

Lost the older 3 TB WD My Book Essential and a 5 TB Seagate Expansion Desktop Drive.

Things I've tried that haven't worked so far:

• Neither drive is visible in Disk Utility
• SMC reset: https://support.apple.com/en-us/HT201295
• I've looked for Seagate and WD driver updates for Big Sur but nothing is available at the moment
• I've downloaded both the Big Sur compatible Seagate Paragon and the WD Discovery "general" drive management software
• https://www.seagate.com/ca/en/support/downloads/
• https://support.wdc.com/downloads.aspx?lang=en
• Neither drive was visible from the Paragon software
• The WD Discovery software could see the My Book drive but showed it as locked. I've never set a password and from what I've read there is no way to unlock it without the drive booting/already having access
• Downloaded iBoySoft NTSF for Mac but neither was visible

So based on what I've read I either need to get another Mac with an older OS and transfer the contents of the old disks to newer/compatible EHDs, or wait for Apple to patch or wait for Seagate and WD to update the drivers.

I've completely read through this support thread and If anyone has any other suggestions I would love hear them.

Same problem here. I thought i had the problem solved alas no.

Tried mounting with diskutil and looks successful

sh-3.2# diskutil mount /dev/disk2s2

Volume KEV on /dev/disk2s2 mounted

But it gets unmounted straight away

sh-3.2# diskutil unmount /dev/disk2s2

disk2s2 was already unmounted

diskutil list shows it there.

sh-3.2# diskutil list /dev/disk2

/dev/disk2 (external, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *1.0 TB disk2

1: EFI EFI 209.7 MB disk2s1

2: Apple_HFS KEV 999.9 GB disk2s2

This is a bit ridiculous. My time machine backups are there (thankfully not needed post Big Sur) but also all my photos for the last number of years are there and music among many other bits and pieces.

FWIW this is dmesg showing the mounting process

[324962.492944]: USB device 1058110014422000 - Last CDBs 00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:157

[324962.700730]: USB device 1058110014422000 - Western Digital , My Book - detected termination of interfaceNub, currentPowerState 1, provider is non-NULL

[324962.700794]: USB device 1058110014422000 - Last CDBs 00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:000|00000000:157

[324962.701224]: disk2s2: device/channel is not attached.

[324962.701245]: disk2s2: device/channel is not attached.

[324962.701391]: USB device 1058110014422000 - fConsecutiveResetCount = 1.

[324962.701404]: disk2s2: device/channel is not attached.

[324962.701987]: disk2s2: media is not present.

[324962.702302]: disk2s2: media is not present.

[324962.702609]: disk2s2: media is not present.

[324962.702954]: disk2s2: media is not present.

[324962.703000]: disk2s2: media is not present.

[324962.703107]: disk2s2: media is not present.

[324962.703210]: disk2s2: media is not present.

[324962.703306]: disk2s2: media is not present.

[324962.703309]: disk2s2: media is not present.

[324962.703395]: disk2s2: media is not present.

[324962.703484]: disk2s2: media is not present.

[324962.703571]: disk2s2: media is not present.

[324962.703655]: disk2s2: media is not present.

[324962.703739]: disk2s2: media is not present.

[324962.703823]: disk2s2: media is not present.

[324962.703907]: disk2s2: media is not present.

[324962.703989]: disk2s2: media is not present.

[324962.704073]: disk2s2: media is not present.

[324962.704157]: disk2s2: media is not present.

[324962.704239]: disk2s2: media is not present.

[324962.704323]: disk2s2: media is not present.

[324962.704417]: disk2s2: media is not present.

[324962.704501]: disk2s2: media is not present.

[324962.704599]: disk2s2: media is not present.

[324962.704686]: disk2s2: media is not present.

[324962.704771]: disk2s2: media is not present.

[324962.704862]: disk2s2: media is not present.

[324962.704951]: disk2s2: media is not present.

[324962.705035]: disk2s2: media is not present.

[324962.705122]: disk2s2: media is not present.

[324962.705206]: disk2s2: media is not present.

[324962.705290]: disk2s2: media is not present.

[324962.705376]: disk2s2: media is not present.

[324962.705461]: disk2s2: media is not present.

[324962.705544]: disk2s2: media is not present.

[324962.705628]: disk2s2: media is not present.

[324962.705711]: disk2s2: media is not present.

[324962.705796]: disk2s2: media is not present.

[324962.705882]: disk2s2: media is not present.

[324962.705968]: disk2s2: media is not present.

[324962.706052]: disk2s2: media is not present.

[324962.706138]: disk2s2: media is not present.

[324962.706306]: disk2s2: media is not present.

[324962.706417]: disk2s2: media is not present.

[324962.706526]: disk2s2: media is not present.

[324962.706618]: disk2s2: media is not present.

[324962.706710]: disk2s2: media is not present.

[324962.706822]: disk2s2: media is not present.

[324962.706918]: disk2s2: media is not present.

[324962.707007]: disk2s2: media is not present.

[324962.707095]: disk2s2: media is not present.

[324962.707182]: disk2s2: media is not present.

[324962.707273]: disk2s2: media is not present.

[324962.707447]: disk2s2: media is not present.

[324962.707638]: disk2s2: media is not present.

[324962.707756]: disk2s2: media is not present.

[324962.707766]: disk2s2: media is not present.

[324962.707833]: disk2s2: media is not present.

[324962.707882]: disk2s2: media is not present.

[324962.707888]: jnl: disk2s2: do_jnl_io: strategy err 0x6

[324962.707893]: jnl: disk2s2: end_transaction: only wrote 0 of 143872 bytes to the journal!

[324962.708030]: disk2s2: media is not present.

[324962.708143]: disk2s2: media is not present.

[324962.708241]: disk2s2: media is not present.

[324962.708351]: disk2s2: media is not present.

[324962.708750]: disk2s2: media is not present.

[324962.709004]: disk2s2: media is not present.

[324962.709016]: disk2s2: media is not present.

[324962.709026]: disk2s2: media is not present.

[324962.709036]: disk2s2: media is not present.

[324962.709049]: disk2s2: media is not present.

[324962.709061]: disk2s2: media is not present.

[324962.709072]: disk2s2: media is not present.

[324962.713369]: PMRD: assertionsUser 0x50->0x40

[324962.743106]: disk2s2: media is not present.

[324962.743229]: hfs: unmount initiated on KEV on device disk2s2

[324962.743304]: jnl: disk2s2: close: journal is invalid. aborting outstanding transactions

[324962.743639]: PMRD: PowerChangeOverride (ON_STATE->ON_STATE, f, 0x2) tag 0x22e0064

[324962.743646]: PMRD: PowerChangeDone: ON_STATE->ON_STATE

if you have a iPad Pro with usb-c or the lightning usb camera kit (even better) you can connect to the drive and see if it shows up, once it does it will then work again with your CPU (iMac MacBook etc).

This is a part of Big Sur's design been non compatible with older OS, older drivers etc.

Hey there!

Good question. If you didn’t have a backup while on a previous OS version, then you’d have to create a bootable installer with a previous OS, boot from that, erase the HD, then reinstall the older OS. In either case, to downgrade the OS the Mac does have to be erased, so you’d probably want to back it up first.

Once you have the previous OS installed, you can migrate the data back onto your Mac.

How to create a bootable installer for macOS

https://support.apple.com/en-us/HT201372

How to get old versions of macOS

https://support.apple.com/en-us/HT211683

How to erase an Intel-based Mac

https://support.apple.com/en-us/HT208496

How to reinstall macOS

https://support.apple.com/en-us/HT204904

Move your content to a new Mac

https://support.apple.com/en-us/HT204350

Hope some of that helps!

How is the external HD formatted?

Bev, is your bus powered? Can you plug in an external power source to power the drive?