My email was sent back with an error, what does it mean?

Problem: Mail rejected due to RBL.

Cause: Mail can be rejected by our servers if the IP address has been listed as a virus/trojan or spam source, this is for your protection.

Solution: Check on incase the domain or IP address is listed for more detailed explaination.


Problem: Mail rejected due to 451 SPF lookup failure (#4.3.0).

Cause: When one mail server is talking to another mail server and it has SPF protection active then you need a matching SPF record on the server that is originating the email.

Solution: In cPanel you can active SPF in "Email Authentication" section, please include all IP addresses that would be sending mail on your behalf.



  • 7 Users Found This Useful
Was this answer helpful?

Related Articles

What is my ISP's SMTP mail server?

What is my ISP's SMTP Mail Server Normally the SMTP servers listed below use port 25 (default)...

What email solutions are available through Direct Support?

Sending emails is done through SMTP protocol using Authentication. SMTP uses port 25 or...

Backup Mail Service

Client wishing to use a backup mail service we offer one for $168/year ontop of your existing...

I'm unable to send email, what can I do?

We have secure email servers but as part of that you may need to make some minor adjustments to...

I'm receiving so much spam what can I do about this?

If you are receiving spam email then you have several thing you can do. The first would be to go...