As part of a security precaution, Guild Wars 2 players will be required to change their password starting Feb. 7 to be compatible with ArenaNet's recently introduced blacklist of passwords known to be used by hackers to scan for accounts.
ArenaNet previously introduced a red banner display in the game's launcher, encouraging players to change their passwords without making it a requirement; however, those who are using a password chosen prior to the introduction of password blacklisting on Sept. 12 of last year will need to choose a new one starting next week.
In this new system of password security, players will not be allowed to pick a password previously used on their account or tested against any other user account. ArenaNet encourages users to choose a password not previously used for other games and websites in order to maintain its uniqueness.
Check out our interview with ArenaNet president Mike O'Brien on how to make your Guild Wars 2 account as secure as your email.