mail1231c.emails.generalmills.com has no MX records.
Question and response
Question
dig mail1231c.emails.generalmills.com. MX
Answer
The response has no answer records.
Authority
generalmills.com. 900 SOA mgoextdns1.genmills.com. dom\.admin.genmills.com. 15895 900 600 2419200 900
Additional
. 0 OPT ; payload 1220, xrcode 0, version 0, flags 0