cogecoondemand.com has no MX records.
Question and response
Question
dig cogecoondemand.com. MX
Answer
The response has no answer records.
Authority
cogecoondemand.com. 600 SOA ns4.cgocable.net. dnsadmin.cgocable.net. 3496 1800 900 604800 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0