Hi there!
Wesnoth 1.8 and previous versions did not require registered users to validate their forum account registrations before becoming able to log into the MP server with their credentials. This oversight often lent itself to abuse by troublemakers, and it was thus corrected starting with version 1.9.8 of the MP server and MP client code. Wesnoth 1.10.0 was released on January 29th.
In order to clean up the forum database and get rid of useless registrations, we are going to purge old, unused forum accounts (registered before the start of 2012) whose registrations were never confirmed via email, and were never used to log into the official/primary MP server (server.wesnoth.org).
The purge is scheduled to take place on Sunday, February 12th 2012, and it should not incur any downtime for MP or forum users.
The number of accounts affected is close to 2,500, and it’s suspected that most of them are inactive spambot registrations. All of the affected accounts necessarily have a post count of zero, since it’s not possible to post in the forums without logging in, which requires validating your registration first.
Nonetheless, it is also possible a few of these accounts were registered in order to reserve usernames in the multiplayer server. Since we don’t have any way to verify this, it is your responsibility to validate your registrations via email now and in the future! The Wesnoth.org staff and the Battle for Wesnoth Project members will never use your email address to send you spam, nor will it be published for use by third-parties anywhere unless you choose to do so in your accounts settings in the User Control Panel. The use of throwaway addresses is discouraged since it may create a security problem or make it impossible to help you if you ever need to reset your password.
Users who never confirmed their registrations won’t be able to log into the current 1.10 MP server until they do so. We urge you to download and try Wesnoth 1.10-rc1 or log into the forums to make sure your registered accounts still work. If they do not, and you have lost access or forgotten the email address you used to register them, please either contact me directly or send a group PM to the Forum Administrators to request assistance.
Regards
EDIT: Since there seem to be some doubts about this: No, this does not affect UNREGISTERED users in any way whatsoever. There is a difference between an unconfirmed registration and a name that’s never been registered in the first place.

