For those who are unable to send email out using XAMPP, this is what you can to do.

1) login to your localhost or XAMPP mainpage
2) click on the status and verify if the HTTPS (SSL) service is ACTIVATED

If it's not ACTIVATED, do the follow:

1) go to xampp installed folder > Apache > bin > and open php.ini
2) search for ;extension=php_openssl.dll

Remove the ; so that it will be activated.
Save the file and restart your apache service.

Now the configuration part:
Under the setting from your CRM admin > Email setting

input all the desired setting you want for "From name", "From address"

But this is the required part:
1) SMTP Mail Server: smtp.gmail.com
2) SMTP Port : 465 (this is SSL port)
3) check the box on Use SMTP Authentication:
4) Enable SMTP over SSL or TLS? > Set to SSL (for some unknown reason sugarCRM can only use SSL for gmail)
5) Username: urusername@yourdomain.com
6) User password: yourpassword

And it will work.
I have tried to verify what was wrong for the past 4 hours, from network setting on my router to firewall in my server. but it was just the php.ini that was at fault