mail.winteraccess.net has no MX records.
Question and response
Question
dig mail.winteraccess.net. MX
Answer
The response has no answer records.
Authority
winteraccess.net. 1800 SOA dale.ns.cloudflare.com. dns.cloudflare.com. 2396693755 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0