We are testing Exchange Server 2016 mail server. We can connect to user's mailbox via OWA (Outlook Web Access). When testing POP3 mail from Microsoft Outlook (on a non domain-joined PC) we can send test email but can not login to POP3 server. The error message says:
(Log onto incoming mail server (POP3): The connection to the server was interrupted. If this problem continues, contact your server administrator or Internet service provider (ISP))
- Incoming server port: 110
- Outgoing server port: 25 (no encrypted)
Even when I turn off all firewalls, it still cannot connect. I have the same problem with IMAP. Do you have any ideas, please?