Hi, I have a default SQL 2008 R2 instance on a server ABC1, and I setup a virtual DNS name ABC2 that points to the IP address of ABC1. However, I cannot connect to ABC2 with windows authentication using SSMS on the server ABC1 itself, although I can do so from anywhere else. The error message I received was: Login failed. The login is from an untrusted domain and cannot be used with Windows authentication. It seems very weird. Very much appreciate if anyone can offer any help. Thanks in advance.