Though there are various reasons as to why the emails could be marked as spam, this article contains helpful information to make sure that other servers or network do not mark your email as spam.
Use Email Authentication (cPanel >> Email Authentication)
DKIM and SPF
DKIM (Domain Keys Identified Email) and SPF (Sender Policy Framework) authentication can help verify that email comes from a trusted sender. DKIM is a validation system designed to detect email spoofing. It provides a means for your mail server to check the email that comes from a domain is authorized by that domain’s administrators. The email includes a digital signature that your mail server uses to verify the senders public key in their DNS record.
SPF uses DNS records to prevent email spoofing. If an email message uses fake sender addresses, SPF uses the DNS record for the sender’s domain to detect the modification in the email’s header.
cPanel’s Email Authentication features provide information about outgoing messages. This helps the server that receives the messages verify that the email comes from a trusted sender. Both the Domain Keys Identified Mail (DKIM) and Sender Policy Framework (SPF) authentication functions require that you use a DNS server for the domain name. For more information about DNS servers, review the terms of your hosting contract
DKIM
DKIM verifies the sender and integrity of a message. It allows an email system to prove that spammers did not alter an incoming message while in transit (which means that it is not forged) and that the messages that your domains receive come from the specified domain.
To use DKIM, click Enable.
To disable DKIM, click Disable.
Note:
A warning may display that claims that the system cannot verify the server as an authoritative nameserver for the specified domain name. If either of the following scenarios is true, ignore the warning:
- You designated the server as the authoritative DNS server for the domain name, but the change did not yet propagate.
- The server does not view itself as the authoritative DNS server, but outside servers view it as the authoritative DNS server.
SPF
SPF attempts to deny spammers the ability to send an email while they forge your domain’s name as the sender (spoofing). This authentication function adds IP addresses to a list that specifies computers that can send mail from your domains. It verifies that messages that your domains send come from the listed server, which reduces the amount of backscatter that you receive.
To use SPF, click Enable.
To disable SPF, click Disable.
Note
A warning may display that claims that the system cannot verify the server as an authoritative nameserver for the specified domain name. If either of the following scenarios is true, ignore the warning:
- You designated the server as the authoritative DNS server for the domain name, but the change did not yet propagate.
- The server does not view itself as the authoritative DNS server, but outside servers view it as the authoritative DNS server.
Any particular SPF Record to be added depends solely on the host and therefore it is better to read the host guidelines to find out if any particular SPF Record is to be needed.
Other networks mark my email as spam
If email networks, such as Google, Yahoo, or Outlook, mark your server’s email as SPAM, you must identify the reason and resolve the problem. If you have recently resolved an issue with spam on your server or you received a new IP address which previously sent spam, you will need to notify the remote network.
