Mail forwarders are bouncing but mail sent from server is working.

I hope I can explain this clearly:

- Mail sent from a website (via contact form / script) using SMTP settings or PHP Mail will successfully send.

- Mail that is responded to via an email client bounces "Unroutable address".

For example:
- email sent from website that is configured to send submission to: [email protected]

--> Within DA there is NO email account for this address setup. There is a forwarder in DA setup for [email protected] to forward to [email protected]

-> I go onto the website and submit contact form. Mail successfully delivers.
-> I go into my email client and send a message to the same email address (utilizing my ISP SMTP server) and the mail is bounced. The message I get back indicates that it was unroutable.

I can't figure this one out and would greatly appreciate some help debuging it please.

You need to use your SERVER SMTP, not ISP SMTP and authenticate on it.

Regards

Thanks for the suggestion but that is not the problem. My problem is that the SMTP server on my server was not working.

However, I think I solved the problem. My rDNS was not set. I set it and it seems that everything is working as expected.