We running Exchange Online in Hybrid configuration. We cannot send email to Dynamic Distribution lists created on the local Exchange server.
I have followed the instructions at http://technet.microsoft.com/en-us/library/jj150422(v=exchg.141).aspx to allow us to do this.
The Dynamic Distribution list is created based on which OU an AD account is a member of. The Dynamic Distribution List was created in EMC
Steps:
New Dynamic Distribution Group
Specify Organizational Unit
Set filters to Users with Exchange mailboxes and Users with external e-mail addresses
No conditions set - email should go to everyone in the OU
Mail Flow Delivery restrictions Properties: cleared Require authenticated users checkbox
Click Ok to save Distribution Group
Followed the instructions at http://technet.microsoft.com/en-us/library/jj150422(v=exchg.141).aspx to configure an external contact in the Office 365 web portal.
I made sure that the alias for the contact did not match the alias for the Distribution Group.
There are 180 recipients in the Distribution Group.
When I send an email to the external contact I get this error:
Delivery has failed to these recipients or groups:
ExternalContactName
A problem occurred during the delivery of this message. Please try to resend the message later. If the problem continues, contact your helpdesk.
The following organization rejected your message: DB8EHSMHS024.bigfish.com.
Diagnostic information for administrators:
Generating server: mydomain.onmicrosoft.com
DynamicDistributionGroup@mydomain.com
DB8EHSMHS024.bigfish.com #<DB8EHSMHS024.bigfish.com #5.4.6 smtp;554 5.4.6 Hop count exceeded - possible mail loop> #SMTP#
The rest of the error is the transition headers up until the error above they say the message is going through.