I was running the standard checks that Arno gave us to make sure everything is up and running on my computer. I discovered that I couldn’t run “xterm” while connected to lxplus.cern.ch I received the error “xterm Xt error: Can’t open display:”
Thanks to some help from Elim, I found out I was connected via “ssh email@example.com” whereas I needed to be connected to “ssh -X firstname.lastname@example.org”. Sure enough, I connected to ssh -X and was able to run “xterm” without a problem.
If you’re having problems with running “xterm”, try this out and see if it works.