gw64-fastest.uk2.net has no MX records.
Question and response
Question
dig gw64-fastest.uk2.net. MX
Answer
The response has no answer records.
Authority
uk2.net. 3600 SOA dns1.p01.nsone.net. hostmaster.nsone.net. 1731081756 43200 7200 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0