how to use multiple screens

I am having trouble using multiple screens.I have a macbook pro 2014 running 10.9.5 OS.I have a samsung monitor connected to my mac though a hdmi to lightning adapter.I reinstalled parallel tools but still no luck.In windows running on parallel I hot detect and it shows 2 monitors but the monitor with a 2 on it is greyed out.Any help would be much appreciated.

 

Hi StephenA1,

Please go to Virtual Machine Configure (http://kb.parallels.com/117287) - Options tab - Fullscreen - enable 'Use all displays in fullscreen'.
Start the Virtual Machine in Full screen mode ( http://kb.parallels.com/115171 ) and enable multiple displays.