If you can receive mail but aren't able to send this means one thing.....Your internet provider...Are you able to send emails but not receive?
Either your domain is out of disk space, or your e-mail address itself is out. You will need to...Email Trouble Shooting to get your mail working
Email Trouble Shooting Make sure your user name and password is all lowercase. Make sure...How do I create webmail accounts?
To create an email account, take the steps below Login to your control panel and click on...I am unable to send emails to other mail servers
For troubleshooting email delivery issues: Check to see that MX record is set for the recipient...