If you face issues in receiving /sending mails via Outlook/Outlook-Express/Thunderbird, you can try using direct IP in place of incoming and outgoing server.
Also, you can try using port 465 (with SSL) or port 587 (with TLS) as outgoing port. For POP port 995 (with SSL) can be used, and for IMAP port 993 ( with SSL) can be used. (Note: Certificate warning should be accepted by clicking YES)
Do provide us with the results of the following three commands (on Windows platform) mentioned below if you continue to face the issue: