Small grahpics issue

So I have 3 monitors setup for my computer and the client can fullscreen windowed on the primary (far left one), but throws me an error when I try to switch the monitor to either 2(middle) or 3(for right). I can fullscreen just windowed only version of the client if I want to and that seems to work, but not the same as the fullscreen windowed option.

Trying to switch over to one of my other monitors tends to throw this error: http://i.imgur.com/FGMLl26.jpg

Any ideas?

My recommendation for all games is to go fullscreen windowed mode especially if you want access to your other screens otherwise it seems to be an issue within the client itself something unfixable by warmane staff - there maybe a dirty fix somewhere on the interwebs but i cant provide any solution from my esteemed knowledge.