Cannot add Shared Folder using internal *SECOND* HDD

This is not the OS hard drive, but rather a 2nd HDD.

It shows up as /dev/sdb1 in the "File Systems" page, but when I go to the "Shared Folders" page and attempt to "+ Add" folders on it as shared folders it doesn't appear in the drop down list next to "Device".

If I plug in a USB External HDD and mount it, that external HDD does show up in the drop down list.

I should note that /dev/sdb1 is formatted with an ext4 file system and was formerly used on an OMV 2.x installation.

I'm trying to upgrade to OMV 3.x and I have hit this stumbling block. Before I resort to making a new logical volume on my OS HDD, copying the contents of /dev/sdb1 onto it, and deleting then recreating the filesystem on /dev/sdb1 via the OMV GUI, I wanted to ask here and see what wisdom I could gather.

My fear is that after doing all that repartitioning and moving files around and recreating the file system in the OMV admin GUI I'd find it STILL wouldn't work....

Tried and failed before I posted.

Also attempted:

• Remove in CLI and mount in CLI
• Remove in CLI and delete references in config,xml and fstab then remount in GUI
• As above but before remounting I added OMV_FSTAB_MNTOPS_EXT4="defaults,nofail,user_xattr,noexec to /etc/default/openmediavault, re add in GUI (I was using This Thread as a guide - BTW I couldn't use etc/init.d/openmediavault-engined restart to restart because it doesn't exist, so I used omv-initsystem before remounting)

Thanks anyway.

Anyone else?