This just started the other day. All new mailboxes do not work. Everything is set up correctly but I received this bounced back message. There was a SMTP communication problem with the recipient's email server. Please contact your system administrator. The services and the server have been restarted since this has been happening. Is there something I am missing that would be causing this? Does anyone have a similar issue or had it in the past?
I didn't find the right solution from the Internet.
Blockchain Use Case