pochta7.mtw.ru has no MX records.
Question and response
Question
dig pochta7.mtw.ru. MX
Answer
The response has no answer records.
Authority
mtw.ru. 43200 SOA mtw.ru. hostmaster.mtw.ru. 2020001277 3600 3600 1209600 43200
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0