Office 365 -Exchange 2003 issue – NDR 5.4.6 Routing Loop

I had this problem with one of my office 365  costumers  when i tried to send emails from on premises mailbox to the cloud and got this NDR:

Your message did not reach some or all of the intended recipients.

Subject:    test from on premises 4
Sent:    2/27/2013 7:10 PM

The following recipient(s) could not be reached:

  i386 user1 on 2/27/2013 7:10 PM
A configuration error in the e-mail system caused the message to bounce between two servers or to be forwarded between two recipients.  Contact your administrator.
< #5.4.6>


First I created on the  Exchange 2003 server  an SMTP connector that will route any mail destined for * to the hybrid Exchange 2010 server

Then I changed the SMTP address space to Internal Relay instead of Authoritative Exchange 2003 will send the message  through the Exchange 2010 server using the TLS secured connection.

Exchange 2003 connector properties :




Exchange 2010 – Accepted domain



Good luck!

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