Can send locally but not externally.
Typically this is a relay error. Make sure your mail server can relay for your MailMessage.From address.
If that address is valid, you may need to allow relaying for your specific IP Address,
or first authenticate before sending the email. See
4.3.5 Not a gateway or local host.
3.8 How do I authenticate to send an email?
for more information.
Copyright © 2004 Contact: Dave Wanta.