DIFFICULTY MOUNTING REMOVABLE DRIVE

[Maurice Murphy]

For some reason or other, all of a sudden, I am unable to mount my large 
removable drive.  I get the following message when I attempt to mount 
the drive:

maurice at MAURICE:~$ sudo mount -a
fusermount: mountpoint is not empty
fusermount: if you are sure this is safe, use the 'nonempty' mount option
FUSE mount point creation error: No such file or directory
Unmounting /dev/sdb5 (MyBackups)

What should I enter in terminal to use the 'nonempty' mount option?
maurice at MAURICE:~$ sudo mount -a
fusermount: mountpoint is not empty
fusermount: if you are sure this is safe, use the 'nonempty' mount option
FUSE mount point creation error: No such file or directory
Unmounting /dev/sdb5 (MyBackups)

I am using ntfs-3g and have verified all the steps necessary for its 
installation.  My /etc/fstab seems OK.  I have made no changes there.

I am pretty sure that my sources.list is OK, although I get a bit dizzy 
trying to read all the lines!

Does anyone have any suggestions as to how I might resolve this problem?

Many thanks in advance, Maurice