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.



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