I just installed Ex2k w/ sp3 on Win2k Adv w/ sp3. I have no problem sending out e-mails, and same domain users are able to Send and Receive e-mails perfectly. Problem is mails that are coming from external domain. When I try sending an email from yahoo or my other pop3 account, I get "The following recipient(s) could not be reached:'me@mydomain.com' on 6/16/2003 10:25 AM 553 sorry, that domain isn't in my list of allowed rcpthosts (#5.7.1)". But funny thing is when I test with hotmail, my Ex2k is able to recieve mails. I thank you guys in advance for help.