This task in the software is used only for multi-displays connected to a single system. i.e., calibrating the display connected to a system with that of the already calibrated display connected to the same system. This concept is called Matching of display.
First, to know if your system is connected with multiple displays correctly, right click on your system desktop and select properties. Then, open the settings tab as shown in the figure.
click Identify to check if all the displays are shown correctly.
click Apply, then OK to confirm proper display connection.