Help:Unified login

The Wikimedia Foundation operates many editable wikis in many languages. Traditionally, users had to create separate user accounts on each wiki. This made it more difficult to participate across many wikis, especially as Wikimedia Commons made multimedia integration more essential and Wikidata became the central wiki for interwiki links.

Your global account solves these problems by reserving your name on all wikis (so nobody else can impersonate you), and automatically creating your local account when you visit a wiki you've never visited before.

You can use Special:CentralAuth to view details about your global account. The email address and password you configure on Special:Preferences will be used on all wikis. This means that you will be able to log into any public Wikimedia project with just one single username and password.

Registering a username on any public Wikimedia wiki automatically reserves that name on all the others; this means different users can no longer register with the same account name on different wikis. Users only need to set and confirm their email address in one account. Changing the password in any wiki changes it in all wikis accordingly. Special:UserLogin now logs the user in to every unified wiki simultaneously, noting that navigating away from the login page before it is fully loaded may result in incomplete login (i.e. this uses JavaScript and users may not log in to all wikis successfully).

Additional wikis will be added to the user's login the first time they are visited, and a local account will be created on that wiki. For example, a regular user at Commons and German Wikipedia does not automatically login to English Wikibooks, but if that user visits English Wikibooks once while logged in, they will then log in to English Wikibooks each time (to see which wikis you have logged into, see Special:CentralAuth).

• Some things are still local:
  • User rights are mostly local, which means that administrators do not have administrator access everywhere. Global groups such as global rollback, global sysop, global interface editors and global IP block exemption can be requested at Steward requests/Global permissions.
  • User preferences are local, although the email address only needs to be set and confirmed in one place. You can continue to have different preferences on different sites. It is possible however to set global preferences if you so wish.^[1]
  • Blocks are local, meaning that users blocked on one wiki can still edit other wikis, unless otherwise blocked by an administrator on that wiki. However, if an account is globally locked or globally blocked, then that applies to all wikis.
• Users can still have differently named accounts on two sites; however, these accounts cannot be linked together into one global account.
• The global account system is only available for open Wikimedia projects; sites which run on the MediaWiki software but are not operated by the Foundation will continue to have separate account systems, even if they installed CentralAuth extension, which is responsible for the unified login system.

Currently Wikitech is being migrated to SUL. Check your Special:CentralAuth to see if you have an unattached Wikitech account. If you have, then you may get this error message when you try to log in to any wiki where your account does not already exist:

Auto-creation of a local account failed: Cannot create account: The username is already in use. Please pick another name.

The message is made by MediaWiki:Authmanager-authn-autocreate-failed and MediaWiki:Centralauth-account-unattached-exists. You may see it in the language of the wiki. Try merging the Wikitech account at wikitech:Special:MergeAccount to fix the problem.

Yes. You can request renames by using this form or by placing a request at Steward requests/Username changes, where a steward or a global renamer will look into your request. See the global rename policy for details.

If they're on different wikis, then it is theoretically possible to merge them into one global account with a consistent name, but the process is complicated and rarely done. If they are on the same wiki, then it is outright not possible to merge accounts.

No. You will have to wait the appropriate amount of time and do the appropriate amount of edits after first logging into each particular wiki, before getting autoconfirmed status.

No, this is not possible. Fishbowl and private wikis are not part of the Unified Login system and use their own separate accounts.

This is not a failure of the unified login system, it is typically a related issue of a browser preventing the login through restricting cookies being set for your login.

Noting that each sister set of wikis has a different base domain name, eg. wikipedia.org, wikimedia.org, wikisource.org, etc. and the cookies are set accordingly. If your login constantly fails, you should consider lodging a Phabricator bug report.