Applies To: Windows Server 2008, Windows Server 2008 R2
The Windows Server® 2008 family supports unauthenticated access, which means that user credentials (a user name and password) are not required. There are some situations in which unauthenticated access is useful. For more information, see Unauthenticated access (http://go.microsoft.com/fwlink/?LinkId=73649). (This information describes unauthenticated access as it is supported in Windows Server 2003.)
When you enable unauthenticated access, remote access users are connected without sending user credentials. An unauthenticated remote access client does not negotiate the use of a common authentication protocol during the connection establishment process and does not send a user name or password.
Unauthenticated access with remote access clients could occur when the authentication protocols configured by the remote access client do not match those configured on the remote access server. In this case, the use of a common authentication protocol is not negotiated and the remote access client does not send a user name and password.