neustarmedia.us has no MX records.
Question and response
Question
dig neustarmedia.us. MX
Answer
The response has no answer records.
Authority
neustarmedia.us. 86400 SOA udns1.ultradns.net. networkers.neustar.biz. 1308318890 86400 86400 86400 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0