I have simple server Windows 2008 Standart SP2 with Exchange 2007 with apply SP1. Only one DC and one Exchange server (not exist Edge) in the same server.
I have first distribution group by name "firstname.lastname@example.org" with 10 users. Working with internal and external mail correctly.
I have second distribution group by name "email@example.com" with 3 users. Working with internal mail correctly, but external mail delivery failed 2 from 3 users. Only 1 users proclaims that external mail delivered correctly. Those 3 users they are too member of distribution group firstname.lastname@example.org" .
I am not found in the eventlog any problem with Exchange server. Any user and any distribution group not check the box "Require that all senders are authenticated."
Any ideas on how to solve the problem?
New informations for this case
i am have enabled delivered NDR report in hub transport. If you request a return receipt in Outlook, then will deliver the answer:
"Your message has been successfully relayed to the following recipients, but the requested delivery status notifications may not be generated by the destination. email@example.com"
I recently tried create new user with name firstname.lastname@example.org and adding member of distribution group with name email@example.com. I sent external mail to firstname.lastname@example.org and i discovered through "Outlook Web Acces" that delivery external email to the mailbox of email@example.com failed (email has not been found in any folders and antivrus not used). Thick mail client MS Outlok he has never been used for this user. I am verified by use with another user acount through MS Outlook, you see that firstname.lastname@example.org is member of distribution group with name email@example.com. Then i am adding new user firstname.lastname@example.org to distribution group with name email@example.com and i sending testing external e-mail, everything was alright (successfully relayed all members of distribution group firstname.lastname@example.org). Delete and re-create the distribution group with name email@example.com had no effect on the functioning of.
I recently tried create new distribution group with name firstname.lastname@example.org and adding to member same users as have distribution group with name email@example.com, then i sending testing external e-mail to firstname.lastname@example.org, everything was alright (successfully relayed all members of distribution group email@example.com).
I tried now delete distribution group with name firstname.lastname@example.org and next step functional distribution group with name email@example.com rename firstname.lastname@example.org. This action had no be effect on the functioning of. Only one from many users external mail has been delivered successfully. :(
Thank you for reply
best regards Alex