How Do I Switch Primary Adapters?

I searched and could not find an answer to this particular problem. Originally, I had only one monitor set up on my computer and when I played Supcom2 this was obviously my primary adapter with the secondary disabled in the game's settings. Then I added a bigger monitor and I wanted to use the bigger one as my primary and the old one as the secondary.
Problem:
When I switched to use the bigger one as my primary in the Display Properties in Windows, Supcom2 won't run at all. When I switch back to the smaller (original) monitor as the primary, it runs fine. I tried seeing if there was somewhere in the game's video settings where I could change this but there was no option to change what the primary adapter was. I'm getting the feeling the only way to get this right is to uninstall the game and re-install it while the bigger monitor is the primary. But I really don't want to have wait for Steam to do its crap all over again as my internet is slow. (I know what Steam is for and why it's a good thing, but I flippin hate it all the same, (just thought I'd put that out there)) Is there any way to do this without uninstalling and re-installing the game?|||Start Supreme Commander 2 with the /safemode launch option, that should fix it.|||Deleting your gameprefs file (in your appdata\local\gaspowered\supcom2 folder) and then launching the game will reset all of your settings. It should allow you to launch the game with your other monitor as the primary. I have to do that every time i go from using duel monitors to a single monitor.|||-The-Baron-|||-The-Baron-|||Spooky|||c3po|||c3po|||Spooky|||Thanks guys! Worked perfectly.