Hi, Might be a newbie question... We physically moved our exchange server to another location.The system got a another public ip address (say 12.23.34.45). If we want to send an email we got the message: Relaying denied. IP name lookup failed (12.23.34.45). Never had that problem on the old location with another public ip address (98.87.76.65). Move back is not an option. Never needed to specify 98.87.76.65 previously (can't remember).Anybody an idea how to solve this problem? Thanks in advance, Gerard

Can you provide more details? Is your server itself on public IP? How about other components like Domain Controller? Are they on public IP as well? What is the SMTP configuratoin on the server? Is it updated to include new IP address for relay?

More information see: http://forums.microsoft.com/TechNet/ShowPost.aspx?PostID=3958390&SiteID=17(made another thread - more an admin issue(?!)). Thanks for your help. Gerard