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.
