smtp03.cidc.telus.com has no MX records.
Question and response
Question
dig smtp03.cidc.telus.com. MX
Answer
The response has no answer records.
Authority
smtp03.cidc.telus.com. 86400 SOA dns1.cidc.telus.com. support.cidc.telus.com. 2025020300 28800 7200 604800 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0