FTM (which I am new to) is unlike software that most people use these days. The functionality seems very 90's or even '80s.
Anyway, what they choose to not tell you is you probably have to download an FTM update. When I get that quaint "your login is bad BAD" message, I usually quit, relaunch, and download the unannounced update.
(I'm on a Mac, its under the menu item Family Tree Maker 2 > Check for Updates. Not sure where the Windows version is.