Failed to mount USB drive (Samsung 4TB) - how to fix this?

[m654321]

My Samsung 4TB external USB drive fails to mount. I want to mount it as I want to wipe it clean and reformat it.
When I open the file manager, the name Samsung appears under DEVICES, but a notification on the display says "Failed to mount "Samsung".  An operation is already pending".

However, using the terminal, this USB drive is detected by the command inxi -d, output from terminal shown as ...

Code:

ID-2: USB /dev/sdb model: M3_Portable  size: 4000.8GB

I think the reason for the failure to mount was that it was accidentally unplugged during a data transfer from PC to the USB drive, so I assume it now has corrupted sectors which I suppose is the cause of the problem. I'm hoping I haven't lost the use of this drive for good ... :'(

I should add that when I 'eject' this USB drive under DEVICES, it never completes the process, so I have to unplug it before its properly 'ejected'.  When I unplug it I get the following message in the notification that appears on the display:

Code:

Failed to mount “SAMSUNG”
Error mounting /dev/sdb1 at /media/SAMSUNG: Command-line `mount -t "ntfs" -o "uhelper=udisks2,nodev,nosuid,uid=500,gid=500" "/dev/sdb1" "/media/SAMSUNG"' exited with non-zero exit status 13: Error reading bootsector: Input/output error
Failed to sync device /dev/sdb1: Input/output error
Failed to mount '/dev/sdb1': Input/output error
NTFS is either inconsistent, or there is a hardware fault, or it's a
SoftRAID/FakeRAID hardware. In the first case run chkdsk /f on Windows
then reboot into Windows twice. The usage of the /f parameter is very
important! If the device is a SoftRAID/FakeRAID then first activate
it and mount a different device under the /dev/mapper/ directory, (e.g.
/dev/mapper/nvidia_eahaabcc1). Please see the 'dmraid' documentation
for more details.

So, how  can I force a mount so that the drive can be reformatted?
Many thanks, as always, for any help with this.

Mike