spfe.itsc.cuhk.edu.hk has no MX records.
Question and response
Question
dig spfe.itsc.cuhk.edu.hk. MX
Answer
The response has no answer records.
Authority
itsc.cuhk.edu.hk. 600 SOA ddi-gm1.itsc.cuhk.edu.hk. hostmaster.cuhk.edu.hk. 201710697 900 300 1209600 600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0