Campaign problems

[Achen of Pella]

Whenever I start up a campaign after choosing what faction I would play it goes to the loading screen like normal, but like a second when the loading pops up I go back to my desktop and the program quits. Does anyone know what the problem is and how to fix it. If someone could help it would be greatly appreciated.

[Justinian Australis]

I am no expert but it sounds like you have to re install to fix it as some files must have been changed somewhere that causes that to happen. This has happened to me before a few times and it usually is moddified files that aren't correct to enable to game to run properly.