_spf.openfind.com has no MX records.
Question and response
Question
dig _spf.openfind.com. MX
Answer
The response has no answer records.
Authority
openfind.com. 60 SOA dns.openfind.com.tw. cloud_se.openfind.com.tw. 2025111301 10800 3600 604800 10800
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0