do you have the issue if you run gnome-mount -v -b -d <device> locally? do you try to use a remote client? could be a policykit issue there is several bugs there about credential not working over ssh and similar
do you have the issue if you run gnome-mount -v -b -d <device> locally? do you try to use a remote client? could be a policykit issue there is several bugs there about credential not working over ssh and similar