I've been running 3 monitors for the last 12 years, and I can tell you one thing: The fix is stupid. First, you go into Windowed (Not borderless), and then drag it onto the monitor you want. As per any window, drag the window to the top of the screen for the default "Maximize window" function so that it centers on the screen. After that, switch it back to Borderless. Also, please consider if you have recently added (or subtracted) any monitors from your setup, as well as if you have unplugged any from your computer, as that will change your monitors' number assignments. Finally, go into your monitor settings to make sure number assignment is the same, especially AFTER you've updated any video drivers, both for your computer in general, as well as from your GPU manufacturer, as this may sometimes switch the assignments around, as well. EDIT: Side note here. A lot of games have a different number labels for your monitors. For instance, my primary is 1, left monitor is 2 and right monitor is 3. However, in Destiny and other games, my primary is 0, left is 1 and right is 2.