Was playing, then resolution extended MUCH too far to right. Won't fix now

I just reinstalled Rome Total War, the patch, and the mod for EB. I was playing in the campaign and the first battle I started I went AFK for a minute. I left when the game "zoomed" in on the general beseiging the city. Next thing I know when I get back is the battle speech generals give before the battle is weird looking.

In fact its like the screen has extended onto a second monitor that doesn't exsist. So the game is extremely narrow and half of the game screen is missing on my single monitor.

Not only that, when I exit the battle the screen didn't change back so both the campaign map and main menu were... over extended. I tried restarting the game but now it won't go away at all! Help!

Check your battle resolution and make sure it's the same as your campaign resolution (check this BEFORE loading a campaign). That sounds, to me, like the probable cause of your problem.

Open preferences.txt and manually edit both the campaign and battle resolutions: make sure that these are the same as the maximum resolution of your monitor. That should definately work, as this solution also takes care of the possibility that your monitor has a rather odd height x width dimensions (such as 900 x 1440). Those 'odd' dimensions can cause some problems, as the game doesn't detect them itself.

Alternatively, you can do what I did, which was to turn off my monitor and turn it on again. That resets the monitor video settings and restores normal video resolution. You don't even have to quit your battle, just pause, turn off, turn on, resume. Almost guaranteed to work since I've helped 3 friends who had such problems during EB.