Displays Secondary screen issues in windows 10

I recently built a little lcd display in a box for my son so he can have MSI Afterburner display information on it while he's gaming.

It works brilliantly but when he restarts his pc afterburner starts with windows but the GUI doesn't automatically pop up.

If you click on its icon in the task bar it appears but back on his main screen not his mini screen.

I tested everything on my pc and it worked under windows 7 using Afterburner and EVGA precision but he has windows ten and it wont play ball.

Anyone got any ideas?

 

Anyone?

 

What connections are you using for the main monitor and little LCD box?

 

DVi for the main and HDMI for the mini as that is all it has, lad needs to use the TV's HDMI for his 360.