I tried to display Grid Lines (Overlay -> Grid Lines) in ENVI 4.6.1 (Linux RedHat 32bits). Once the procedure is loaded I got this message error (in a pop-up window): An error was caught in the main display event handler. Error: Variable is undefined: B_XTICKV. I tried several times, I got the same at each try. what-s going wrong with my data? thank you for any feeback