In order to improve the deliverability of email messages, DKIM and SPF need to be valid.
DKIM verifies the sender and the integrity of a message. In addition, it allows an email system to prove that spammers did not alter an incoming message while in transit. DKIM also verifies that the messages your domains receive come from the specified domain.
SPF verifies that the messages your domains send originated from a listed server. In addition, it provides a list of servers approved to send mail from your domains.
DKIM and SPF are associated with a domain. Google, along with most public email hosts, require that DKIM and SPF are set before they receive email from your domain.
Click on the links below to get instructions on how to set DKIM and SPF. They may already be set. The links will also show if DKIM and SPF are correctly set.