Gold Edition: Claims I have 1.3, can't play online.

[Trentest0]

I have the Gold Edition, so people have endlessly been telling me that the game is automatically patched to 1.5 in it. But in Rome Total War, in the options menu, it says I have 1.3. Any attempts to update fail with the usual "Gold edition not compatible"

Just how on Earth do I fix this?

[Brusilov]

Where did you get the Gold Edition from? Is it an official version of the game or is it something else.