Unable to send (SMTP) using eM Client while receiving (POP3) works with windstream.net

Mail
1

Unable to send (outgoing mail using smtp.windstream.net) with eM Client while receiving (incoming mail POP3 using pop.windstream.net) works fine.

Using Current version of Windows 10 Home Version 1703 OS Build 15063.483

Fix option after diagnostics from eM Client Account option fails after trying various ports (425, 587, and 25) with different combination of security policies (Don’t use secure connection, Use SSL/TSL if available, Force usage of SSL/TLS, and Use SSL/TLS on special port - legacy) and authentication options (use identity credentials or use these credentials).

Please help and share your experience/resolution. 

Using the latest eM Client 7.1.30794.0

Both SMTP and POP3 used to work before. About a moth ago both stopped working. Upgraded to eM Client 7.1.30794.0
Now POP (incoming) works while SMTP (outgoing) has problem.

2

The problem was resolved after contacting windstream.net to move my email address to white-list. They black-listed it as I was not using Windstream internet service and used TWC.COM Internet service to access my Windstream email. I do not think it was correct for a provider to block access while using another provider unless the other provider was generating spam. People travel, access email from work, friend’s home, hotel, airport, or elsewhere. Unilaterally black-listing email without investigating if spam or genuine access is to stop.