I keep being sent to various articles on help.godaddy.com
However, your domain expired 6 months back!
help.godaddy.com uses an invalid security certificate. The certificate expired on August 13, 2017, 7:33 PM. The current time is December 3, 2017, 3:22 PM. Error code: SEC_ERROR_EXPIRED_CERTIFICATE
I am seeing a similar issue with the pop.secureserver.net. The cert is within the valid date but outlook says the target principal name is incorrect.