The development team implemented some new tech on Monday in preparation for the new multiplayer-version of the game. Unfortunately, this update caused an unexpected issue with the connection between the game server and the old, web-based version of the game. The end result is the server error the community is currently experiencing.
After assessing the situation, we have determined that the time spent fixing this issue would have a significant impact on releasing the new multiplayer-version of the game next week. With this in mind, we’ve decided that the best course of action is to disable the remaining web-based game functionality earlier than we had originally intended. Effective immediately, www.pokemontcg.com/tcgo will no longer provide access to the Pokémon TCG Online. Please see this thread on the forums for more information about the upcoming multiplayer release.
Code redemptions that unlock items in the previous web-based version will still grant the items to your account but those items will be inaccessible until next week’s release of the new version of the game. Code redemptions for theme decks will continue to unlock theme decks in the downloadable Trainer Challenge. Booster pack codes will continue to grant booster credits, but booster credits cannot be used until after the new version has been released.