dns.media4web.cz has no MX records.
Question and response
Question
dig dns.media4web.cz. MX
Answer
The response has no answer records.
Authority
media4web.cz. 864 SOA dns.media4web.cz. hostmaster.nethost.cz. 2026021302 10801 3600 3600000 864
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0