You have an existing Ancestry account, otherwise you wouldn't be able to post on the board.
In order for FTMM to be "on-line", it requires you to be logged/signed-in to your ACOM account from the FTMM program.
If the FTMM application is open, quit it.
Then fire it back up, and log-in, using your ACOM username and password. See dashboard on the right side and "Login", if the program doesn't prompt to log in to your Ancestry Account.