Same here. I have been researching and testing for several hours now and I still cannot get the form to send. Tried your solution above, and still get the dreaded Red Failed message. My ISP has confirmed all setups are correct and regular emails via email clients all deliver perfectly. I have Contact Form DB installed, so capturing emails but I still need the email sent so that various users on the site get informed that an email has been sent.

Aaarghh! Any other ideas?