ns6.iis5.net has no MX records.
Question and response
Question
dig ns6.iis5.net. MX
Answer
The response has no answer records.
Authority
iis5.net. 3600 SOA ns.iis5.net. lovekt.hotmail.com. 156 54000 600 86400 3600
Additional
. 0 OPT ; payload 4000, xrcode 0, version 0, flags 0