how do i connect my desktop monitor to my laptop as a dual
 

I plugged my desktop monitor to the blue serial port of my laptop and am trying to display the laptop contents on both monitors but it doesn't do it. What settings do i need to play with for this?

usualy there's a button on your keyboard some place to turn it on
like i mine i have to have hit FN then F10 (fn conltrols laptop functions)
changes from laptop to laptop