forwardcorp1d.mail.yandex.net has no MX records.
Question and response
Question
dig forwardcorp1d.mail.yandex.net. MX
Answer
The response has no answer records.
Authority
mail.yandex.net. 300 SOA ns3.yandex.ru. sysadmin.yandex.ru. 1772139906 900 600 3600000 300
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0