Thread:Project:Support desk/How to make single registration for 2 wikis?/reply (2)

You only need Extension:CentralAuth if you have a lot of users already that need to manually merge accounts.

If you are starting new, Manual:Shared database should work fine. Choose one as the main wiki and make sure you are setting all of these (read the manual page to know which values they need): $wgSharedDB = .. $wgSharedPrefix = .. $wgCookieDomain = ..

If that doesn't work, then we shall fix that. Looking for another solution is unlikely to help you. Please elaborate on "doesn't do it right". What does it do? Show errors? Launch rockets instead of sharing tables ;-) ?