Is this volume used by time machine? 6.2.1 should help address that.
If not, something in macOS is holding onto the volume.
Try this to see two things using terminal, just paste these in. You will need your admin password.
First conform that 6.2.1 is the driver that is loading:
sudo kextstat -b com.softraid.driver.SoftRAID
Second, unmount your volume. Wait a few seconds. then run this to see what is active on the volume:
sudo lsof /Volumes/myDrive
(myDrive is the name of your volume. Change to your volume name. If you have a space in the volume name, temporarily rename it, so it has no spaces, so you can use this format of the command)
matt@Matts-MBP-2 ~ % sudo kextstat -b com.softraid.driver.SoftRAID
Password:
Executing: /usr/bin/kmutil showloaded --bundle-identifier com.softraid.driver.SoftRAID
No variant specified, falling back to release
Index Refs Address Size Wired Name (Version) UUID <Linked Against>
256 0 0xfffffe0006e9c5f0 0x4000 0x4000 com.softraid.driver.SoftRAID (6.2.1) FB767E03-2D35-3959-B63A-317BE3F1D3EA <16 5 4 3>
matt@Matts-MBP-2 ~ % sudo lsof /Volumes/Thunderbay
lsof: status error on /Volumes/Thunderbay: No such file or directory
And then if I pull the cable from my MBP, I get the error.
Best suggestion I have is running
lsof /Volumes/volumename when the volume is still mounted (and nothing using it) and see if anything shows open.
Lets confirm that 6.2.1 is actually the driver that is loading:
sudo kextstat -b com.softraid.driver.SoftRAID
I think the actual bug is Time Machine is not letting the volume "close" when unmounted.
Maybe there is a terminal command to close the volume, I can dig around.
@softraid-support I think I will disable TM for now and see if I still see the notification.
@softraid-support Seems to be something else because I have disabled TM and it still gives the error when I unmount and disconnect the cable.