Error: SMTP Not Working in Python

What's Causing This Error

It is a generic error that can occur for various reasons mentioned below.

1. Invalid SMTP configurations.
2. Invalid username/password.
3. Invalid use of SSL or TLS.
4. Configuration issues with Python.

Solution - Here's How To Resolve It

Given that the error is a generic Python SMTP error, there is no proper solution. However, you may try the solutions mentioned below to try and resolve the error.

1. Ensure that you're trying to connect to the correct SMTP host on the correct SSL or TLS port (as per the host's guidelines).
2. Verify that you've provided the correct username/password.
3. In rare cases, if you've not installed Python correctly, the mail classes may not get initialized correctly. I've personally encountered this error and found that re-installing Python to the latest version fixes the error.