USB flash drives not registering unless Thunar is running

[Ralf Mardorf]

On Tue, 9 Feb 2016 11:08:27 -0800, MR ZenWiz wrote:
>On one of my Xubuntu 14.04 machines, when I plug in a USB device, it
>fails to mount or register unless I am running Thunar.  If I start
>Thunar after inserting the device, I still have to click on the device
>icon to have it show up (as in df, accessible from the command line,
>in /media/<usr>/, etc.).
>
>This only happens on my home desktop.  My work desktop and laptop have
>no trouble with these.
>
>I suspect it's a setting somewhere, but I have no idea which one.
>
>I have done logouts, reboots, etc. and nothing seems to help.

Did you take a look at all available settings provided by running
  xfce4-settings-manager
?

Xfce4 most likely handles this using GVFS, since it's not installed on
my machine, I can't tell you, if there are entries provided by the
xfce4-settings-manager options when GVFS is installed. Since it's
GNOMEish crap, perhaps there are settings provided by dconf. Xfce4 is
based on a human readable config, but GVFS most likely is addicted to
the binary config dconf.

Perhaps (I don't know) this does help:

http://askubuntu.com/questions/15262/graphical-editor-for-gsettings-dconf