Solved; that was quick. :-) For other reasons, /tmp had incorrect permissions. Changing them with "chmod 1777 /tmp" solved the problem. The hint was this post, https://www.centos.org/modules/newbb/viewtopic.php?topic_id=41813&forum=56 , which described other symptoms I also had: "gconf-sanity-check-2 exited with status 256", and "The configuration defaults for GNOME Power Manager have not been installed correctly". Thanks to jeepster for his post. -- Yves Bellefeuille <yan at storm.ca> "Simply put, E=mc^2 is liberal claptrap." -- Conservapedia.com