_netblocks2.bouyguesbox.fr has no MX records.
Question and response
Question
dig _netblocks2.bouyguesbox.fr. MX
Answer
The response has no answer records.
Authority
bouyguesbox.fr. 900 SOA primary.localdomain. dnsextmaster.bouyguestelecom.fr. 1466 10800 3600 2419200 900
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0