I have an Exchange 2007 (SBS). When I try to send mail to a certain domain, it's mail server tries to verify my email adress by callback.
I then get an error report from my Exchange Server stating the following:
mx-04.sil.at #550-Callback setup failed while verifying <*********@***.at> 550-Called: 188.8.131.52 550-Sent: MAIL FROM:<> 550-Response: 550 5.5.0 Sender domain is empty. 550-The initial connection, or a HELO or MAIL FROM:<> command was 550-rejected. Refusing MAIL FROM:<> does not help fight spam, disregards 550-RFC requirements, and stops you from receiving standard bounce 550-messages. This host does not accept mail from domains whose servers 550-refuse bounces. 550 Unknown sender ##
I guess this is the bottom line: sil.at - This host does not accept mail from domains whose servers 550-refuse bounces.
How can I enable Excjange to accept the verification request??