Hii,,
we have installed exchange 2013 in exchange 2010 environment.
User's can send email within Ex2010
User's can send email within Ex2013
User's can send email from Ex2010 to Ex2013
But cannot send from Ex2013 to Ex2010(if relay is enabled)
It gets queued and when i removed the message from toolbox with NDR, it says "The delivery to recipients has failed" The recipients email system isn't accepting emails now.
I checked the default receive connector settings on Ex2010 and found that "Exchange server" & "legacy Exchange servers" permissions are checked.
Not sure what i am missing.......
Thanks