There is some work on the servers going on since a few days, mayby they were off when you tried it.
Try again pls. If that doesnt work, make a copy of the "save\Chat" (or the complete "save" folder if you got many settings/screenshots/replays to save) folder from the pt root folder somewhere else on your drive and delete the original one.
If that doesnt work, try VPN. There are cases were people have to switch to a vpn connection even before playing the game for the first time.