interdsl.co.uk has no MX records.
Question and response
Question
dig interdsl.co.uk. MX
Answer
The response has no answer records.
Authority
interdsl.co.uk. 86400 SOA ns1.interdns.co.uk. hostmaster.interdns.co.uk. 1752693663 3600 600 604800 86400
Additional
. 0 OPT ; payload 4000, xrcode 0, version 0, flags 0