Before setup, please try to login WebMail once, to make sure your email address and password are correct!
If connection failed, but it ask for password, it means your password is wrong.
If connection failed, but it does not ask for password, it means it is a connection problem, please try other connection methods (SSL/STARTTLS/No-SSL, etc)
Why are there so many connection methods? Which one should I use?
Most people should try the SSL/TLS connection first. This method should work for 99% of modern devices.
Some country/state/company firewall blocked one or the other ports. Some software/device/versions has bug in one or the other connection methods. That's why people invented different workaround methods. Please try other methods if SSL does not work for you.