I am using IIS 5.0 SMTP Server to automatically send e-mails from a web application to a user&#039;s e-mail address that they supply. Certain domains are not receiving the e-mails, while others are? For example, somebody@abc.com will recieve the e-mail, but someone at somebody@def.com won&#039;t. <BR><BR>It appears to be a network configuration issue, but I can&#039;t pinpoint the problem. When running the web application on my devlopment machine on other networks, all e-mail gets out. However, when my computer is hooked into the network where the application is installed, the e-mail is sparatic.<BR><BR>Has anyone experienced this issue before and if so, how did you go about fixing it??? Thanks.