gmail.com for gmail.
Port: The port used by the SMTP server. Normally 25/465/587. For example: 465 for gmail.
Security: The security used for connecting to the SMTP server. Use SSL/TLS for gmail.
Require Login: Checked if the SMTP server needs you to authenticate before sending emails. Check this for gmail.
User Name: The user name required to authenticate with the SMTP server. For gmail, its your email address.
password: The password required ...