mail04.anexia.at has no MX records.
Question and response
Question
dig mail04.anexia.at. MX
Answer
The response has no answer records.
Authority
anexia.at. 86400 SOA anexia.secondns.at. support.anexia.at. 48 10000 1800 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0