I took my eTrex Vista out late yesterday afternoon, could not get a lock, blamed it on the satellite configuration, but suspected it could me more than that. Today I mounted the unit on my dash, drove to work (about 30 min.) and all that time, I not only did not get a satellite lock, but not one satellite showed up even partially on the bar graph. All other functions appear normal; the pop up message "continuing acquiring?" appears normally, and the searching for satellites message remains on the screen during the search. Suggestions?