Any one who has an idea how to reload geonetwork 2.x metadata?

I recently changed the URL and now all thumbnails are pointing to the old URL and therefore not loading.

I cant see anything in the admin interface to indicate that its possible to do so there, and the GAST tool is refusing to run via the terminal (saying "Can't connect to X11 window server using ':0' as the value of the DISPLAY variable").

Saidia oh!