Hi,

We are using outlook.com as the front end for our emails, i.e. we have setup an account to send and receive emails through our provider's SMTP and POP3 servers.

The problem is that we are finding that some emails are bouncing back with the error as below.

Why is this happening and how can we stop it? 

Reporting-MTA: dns;dub0-wss1-s3.dub0.hotmail.com
Received-From-MTA: dns;DUB111-W97
Arrival-Date: Tue, 3 Sep 2013 00:54:34 -0700

Final-Recipient: rfc822;*** Email address is removed for privacy ***
Action: failed
Status: 5.6.2
Diagnostic-Code: smtp;554 5.6.2 Delivery SMTP Error. Command: 7. Response: 550 This messsage is classified as spam (4.8).
. Type=1 (-956218626:896:-2147418113)

Final-Recipient: rfc822;*** Email address is removed for privacy ***
Action: failed
Status: 5.6.2
Diagnostic-Code: smtp;554 5.6.2 Delivery SMTP Error. Command: 7. Response: 550 This messsage is classified as spam (4.8).
. Type=1 (-956218626:896:-2147418113)