smtpout2.byetcluster.com has no MX records.
Question and response
Question
dig smtpout2.byetcluster.com. MX
Answer
The response has no answer records.
Authority
byetcluster.com. 86400 SOA ns1.byet.org. support.byethost.com. 2010111701 28800 7200 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0