Windows LiveID
The Windows LiveID web part allows users to log into the website using their WindowsLiveID logon credentials. In order for this web part to work, Windows LiveID authentication must be enabled and configured properly for the website. This can be done by global administrators in Site Manager -> Settings -> Security & Membership -> Authentication -> Windows LiveID.
More information can be found in the Third party authentication services -> Windows LiveID chapter of Kentico CMS Developer's Guide.