Multiplayer error

[SonicX]

A friend and I have been playing a long epic game on a large map and we both protected our civs with passwords.
But my password for the American empire suddenly doesn't work anymore in the last save and the autosaves (1806 AD), but it does work for a save from 1598 AD before our 5 hour play yesterday.

How is this possible and more importantly, is there anyway I can recover this game because I don't want to play over 100 turns again (those were good turns for me ) and no forsake the game either.
This must be a bug because I didn't change the password for my civ (if that's even possible)

Help wanted

 

[Aacmdan]

I'm having the same problem! It's driving me crazy. I have tried playing 3 different games, and each time, same problem. I tried not entering a password once, and it still asked for a civilization password.