[Will]

Divide by zero is basically what Phoenix-D says; the program tries to divide something by zero, which is basically impossible. If there isn't any code in there to check if something is zero before dividing, or any code to recover from that error, then the default action is to just give up. That's the error dialog you saw, the program giving up and telling you why.

If it has gone through three times, and presumably encountered the same error each time, then you're probably crap out of luck for processing that turn. Rolling back the turn, and having everyone replay an earlier turn probably would get around the problem, since it seems to be a freak incident where somehow either the game file or the player files results in a zero that divides something. I would first try having everyone replay the current turn, and if that doesn't work, roll back to the previous turn and replay that.

--edit: Ok, the filters don't like a certain term describing excrement, so I replaced with another one... you get the idea.