Windows 10 disapearing window

I am running Windows 10 on a laptop, so I only have one screen. With Lockheed Martin P3D Flight Simulator running I have to start another program to sign on to a private server to fly with other club members on line. I start the other program (FS Co Pilot) and the activation window appears very briefly but then zooms off the side of the screen before I can click on the join button. I minimize Flight Simulator, but the other window is not there. It normally appears and stays on top until I click the start button, then I can move it to the tool bar. I have tried everything I could think of that worked in Windows 7 and 8, but no joy. Anyone have a suggestion?
Thanks.