Here's my problem. I have setup a universal distribution group and it is set to receive outside email. It has two members. One member is internal to the exchange org and one member is a mail enabled contact(external address) created in AD. When I send mail to the group alias, few external members do not receive it. However When someone replies to the thread and click reply all then the external member are able to receive the message. Can this problem be resolved and how?

HI, Did you get any NDR for receipients when sending an email to the DL, or what happens when you are sending an email individually to that external mail enabled contact. PLs post the resultor NDR. Thanks