When you configure a two-way external trust, or a two-way forest trust, to use selective authentication for the outgoing side of the trust, but not for the incoming side, the authentication settings appear to be wrong when you view the Properties of the trust in the Active Directory Domains and Trusts snap-in. When you select the Authentication tab from the Properties of either side of the trust, both the outgoing and incoming trusts appear to be using the selective authentication setting.

This behavior occurs because only the authentication settings for the outgoing trust are displayed when you press Properties and select the Authentication tab in the Active Directory Domains and Trusts snap-in. To workaround this behavior, connect to a domain controller in the trust domain and use the Active Directory Domains and Trusts snap-in on that DC.