Unrecognized mount option "x-gvfs-show" or missing value

Short version:

You're not using the parameter as it was designed. Use comment=x-gvfs-show instead of x-gvfs-show...

Long version:

• Don't use the GUI but edit your fstab manually by pressing Ctrl+Alt+T to go to a terminal and typing:

  sudo nano /etc/fstab
  

• find the offending line that shows x-gvfs-show and type comment= in front of it

• Ctrl+X
• Save
• Yes

• reload all entries in fstab:

  mount -a
  

(Or if you just moved over from Windows: don't type mount -a and just reboot for old times' sake) ;-)

I thought I would add this here.

I recently switched one of my pc's from Ubuntu to Xubuntu (not with a clean install).

My external USB hard drives would no longer automount. Checking in gnome-disks they were set to automount but did not.

So I switched to manual mounting (which generates entries in /etc/fstab). The manual mount options were automatically populated with x-gvfs-show (no "comment="), which resulted in a failure to mount.

What I'm suggesting is that the fstab entries with x-gvfs-show may not have been manually generated.