We have exchange 2010 running from SBS 2011. Everything pretty much seems fine MX, DNS and reverse pointer records. But when sending to gmail from one user in particular we are getting the error below. Another user sent to the same gmail address and it worked properly. The other issue is that our MX record is 188.8.131.52 not 184.108.40.206 (IP masked) I'm not sure what to look at for this error. Any suggestions?
mx.google.com gave this error:
[220.127.116.11 12] Our system has detected that this message is likely unsolicited mail. To reduce the amount of spam sent to Gmail, this message has been blocked. Please visit http://support.google.com/mail/bin/answer.py?hl=en&answer=188131
for more information. 9si30080279qam.38 - gsmtp
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