ns2pub.sfr.fr has no MX records.
Question and response
Question
dig ns2pub.sfr.fr. MX
Answer
The response has no answer records.
Authority
sfr.fr. 900 SOA pranspub03.phys.prod. support.dns.sfr.net. 2013017580 3600 900 2419200 900
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0