Failed to update SMTP: deadline has elapsed

[aleph667]

I am setting up a new Rustdesk server pro and trying to configure the SMTP settings, but I keep getting an error message that states that the deadline has elapsed. I've confirmed that Authenticated SMTP is enabled on the mailbox, and I've used the same mailbox for other SMTP services. Any help would be appreciated.

[rustdesk]

You can test from cmd line to confirm if it is reachable. https://github.com/mludvig/smtp-cli