ns-nw.asuscomm.com has no MX records.
Question and response
Question
dig ns-nw.asuscomm.com. MX
Answer
The response has no answer records.
Authority
asuscomm.com. 86400 SOA ns-nw.asuscomm.com. hostmaster.asuscomm.com. 50 28800 7200 604800 120
Additional
The response has no additional records.