Hello, I need your help because I've a problem sending mails to accounts with yahoo.com or yahoo.com.mx domains in Exchange 2000. When I send an email to this domains it remains queued in SMTP Protocol or in SMTP Connector until the time of retransimision is available, but only happens with yahoo, does anybody knows why ??? My actual scenario is: I have installed a NetScreen firewall with NAT address from the public IP to the local IP in my LAN to the Web Server and the Mail Server, these servers have a local IP, but the gateway in both is the local IP from the Firewall which gives the in & out to the publics IP's. Only with yahoo domains happens this. I verify some documents from Microsoft KB but only explain about the FQDN of some domains. I've already change the parameteres for the retransimision time in Exchange but it doesn't works either. Thank you in advance for all the support and comments you can give to me. Best Regards.