ScanDisk Extreme Portable 1Tb won't mount on Mac OS 14.6

Portable SSD Portable | Extreme | Extreme Pro SSD
1

I have a 1Tb portable SSD drive. I have used this for more than a year as a time machine back up (afp formatted). On several occasion, when i plug in another USB device in my iMac M1 i notice that the SSD drive unmounts itself and i get the dreaded “device disconnected warning message”. Usually when this happens, just removing the other USB device and unplugging and reconnecting the SanDisk causes the drive to mount itself again. (some times after a several minute delay)
It seems like you can’t have the SanDisk and another usb storage device plugged in at the same time?? Maybe not enough power available … i dont’ know.
BUT the issue is after the last disconnect, i can’t get the SanDisk to mount.
I have tried.

  • reboot
  • zap pram
  • Boot into safe mode, then connect the sanDisk
  • connect the device to another (older) mac using the USB A->USB-C adapter that came with the drive
  • tried connecting using a different USB-C cable
  • tried connecting to different USB ports on the iMac
  • tried mounting with Disk Utilities

and as you might have guess, none of these worked.
what haven’t i tried (that doesn’t involve a hammer) that you can suggest.

2

Hi @David-62
Have you opened a Support Case? If not opened, for more information, please contact the SD Technical Support team for best assistance and troubleshooting:
https://kb.sandisk.com/app/ask

3

Hi! I’m wondering if you are using a USB hub to connect your external SSD and USB drive. I think the problem is your hub device. Or you may check this guide to fix the SanDisk portable SSD not mounting on Mac.

4

No hub involved. The SSD is connected directly using the USB-C cable that came with the devices.
[An update for anyone finding this old thread]
I made multiple efforts to reformat the drive and eventually pitched it as yet another dead piece of tech. SanDisk support was helpful, but nothing they suggested worked.