smtp01.cidc.telus.com has no MX records.
Question and response
Question
dig smtp01.cidc.telus.com. MX
Answer
The response has no answer records.
Authority
smtp01.cidc.telus.com. 86400 SOA dns1.cidc.telus.com. support.cidc.telus.com. 2025020301 28800 7200 604800 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0