Relay error: Greeting never received - Meaning?

[humptydumpty]

This is the first time I get this specific message. Did the wording change or is this a new type of error? It happened once about 11 hours ago and hasn't repeated since. Sounds like a temp network hiccup. Please let me know if I should investigate this or not.

Notification in Cloudron dashboard:

Email is not configured properly
MyDomain.com
Relay error: Greeting never received

[humptydumpty]

@girish Mailgun. It hasn't happened again (so far). BTW, the notification error listed only two out of ten domains (all using Mailgun).

[nebulon]

Lets wait and see if it happens again first.

[girish]

@humptydumpty what relay are you using?

[humptydumpty]

@girish Mailgun. It hasn't happened again (so far). BTW, the notification error listed only two out of ten domains (all using Mailgun).