You must create a table in your MediaWiki database to hold the OpenID URL mappings. The openid_table.sql script in /usr/share/mediawiki/extensions/OpenID/ should do the trick. Typically you do this using the mysql command-line client, like so: mysql -h yourdbhost -u youradminuser -p yourwikidb < openid_table.sql In your MediaWiki LocalSettings.php, add the following line some place towards the bottom of the file: require_once("extensions/OpenID/OpenID.php"); Theoretically it should work out of the box, but you'll almost definitely want to set the trust root and access controls.