Have you...
Tried turning it off and on again?
IT Crowd for the win.
They need to make another series. (AFAIK they are but they're being slow about it.)
"But Jen, it's an IPhone! For free! I'm not paying Apple a single penny! I'm living the dream!"
"What operating system are you running..?" - "Windows Vista" - "We're dooooooooooomed!"
Ah i'm such a geek that I find that funny...
When you say you crash out, do you actually get into the game or does it crash as soon as it has finished downloading and does nothing more, I may be misunderstanding what you're saying however.
If you have steam it might be a good idea to check that the game is fully working... I will edit this post in a minute with details on what I mean with some instructions since last time I had the error, I was missing some gamefiles.
1) Go to your Steam Games Library
2) Right click on "Mount and Blade Warband"
3) Click on "Properties"
4) Click on "Local Files"
5) Click on "Verify Integrity of Game Cache"
6) Run the game again and hopefully it should have replaced missing files that might have caused this.
I don't hold out high hopes for this but each time something has happened to my Warband this has seemingly fixed the problems so it's worth a shot.