Try this: Go to: System -> Preferences -> Main Menu (In there navigate to Preferences and the check File Management) then Go to: System -> Preferences -> File Management | Media and then set Photos to gthumb.
See what happens then.
Try this:
Go to: System -> Preferences -> Main Menu (In there navigate to Preferences and the check File Management)
then
Go to: System -> Preferences -> File Management | Media and then set Photos to gthumb.
See what happens then.