Hi, Can you please let me know the result of these settings mentioned below: I think it is not working the way it is supposed to. Settings done: On the SMTP virtual server Under ?Relay restriction?, I have checked ?only the list below? and I have given 10.123.124.x and 10.249.11.X subnet Also I have selected ?Allow all computers which successfully authenticates, regardless of above list. With these settings it is working as follows: 1. I can relay external mails from 10.123.124.x and10.249.11.x subnets with or without selecting "my outgoing server requires authentication" on Outlook express 2. If i remove 10.123.124.x and 10.249.11.x from "relay restriction" (as shown in figure enclosed) then i cannot relay from these subnets even if i check " myserver requires authentication" on Outlook express. So i feel authentication part is not at all working. I even tried with "grant or deny access for specific user" option but no luck. Can some help me on this. I just want to allow users to realy who have valid username and password. I am using Exchange 2003 with SP1. I actually tried to send a mail with a snap shot but it seems the list is not accepting it. Regards Praveen R __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com