On Mon, 28 Mar 2011, ken wrote: > Like the error says, you need to specify the display. I.e., on the > remote machine you must set the environmental variable "DISPLAY"... > something like > > (export DISPLAY=192.168.1.42:0.0 & firefox) > > Though this may work, this may well reveal another, different error, one > having to do generally with permissions. But we'll take them one at a time. Do *not* follow this advice. It's bad practice, insecure, and actually more work than being secure, and more likely not to work. Plenty of X servers are configured to not listen on your network interface for example. ssh -X / -Y is your friend, as others have suggested. jh