Since Mojave no longer allows third-party messaging I’m looking to try Spark as an alternative on my iMac. I try to create an account as shown below but it fails with the alert shown. Port 5222 is open I believe. What am I doing wrong please?
It’s asking for a domain, not an URI. Dropping the ‘https://’ should help.
Hi Flow - many thanks but tried that first. Several times. Same result.
Are you able to login with existing account or create account/login in another client?
Can you elaborate on that Mojave change and why do you need Spark? Do you mean Mesaages won’t work with non Apple servers? Well, that’s good news. As Messages never had good xmpp support anyway… 
Mojave no longer supports xmpp accounts in imessages.