Problem: The measure tools return incorrect value
Scale and distance are not correct even though the view's map units are set properly.
ArcView has incorrectly calibrated the screen resolution.
Solution or Workaround
Calibrate your screen resolution. Refer to the ArcView Help document "Calibrate the Screen."
- Why does the Measurement tool display a different value for the same measured distance in a projected view versus an unprojected view?