kerio.tuxis.nl has no MX records.
Question and response
Question
dig kerio.tuxis.nl. MX
Answer
The response has no answer records.
Authority
tuxis.nl. 600 SOA nsauth1.tuxis.net. hostmaster.tuxis.net. 2026030501 10800 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0