We have an internal Exchange 2003 Server and would like to setup a way to have a Distribution List with Internal and External (non-domain) recipients. DL must be available to anyone that wants to send to it. Currently there are three external recipients setup as Contacts and added to DL. When ExternalUser1 sends to DL@domain.com they receive a NDR (5.7.1 Rejected due to SPF policy AND Sender-ID policy) for other External recipients in DL. We do not have any administration over the External Domains to adjust SPF records, and the only work around we have tried without success is to have a User Account for each Contact and then use the User Account in DL and use the Forward to available in ADUC ..... still get a NDR. Suggestions have been made to use a third-party tool to intercept the message envelope and change the Return-Path/Sender but nothing has been implemented or tested. Help?

Hi, Can you send mails to these external users using an internal account.? Is there a spf record present for your server? Leif

Yes can send to them normally from internal and external account, and we do not have an SPF record. The only issue is when a member of DL who is an external User sends to DL@domain.com then the External Recipients fail to receive with NDR being generated.