Tag: Authentication
Why Did My Messages to Gmail Bounce With Error 550, “5.7.26”, “This message does not have authentication information or fails to pass authentication checks (SPF or DKIM)”?
Starting on February 1, 2024, Google has imposed new requirements on bulk senders, including a…
![A diagram of how DKIM messages flow.](https://deliverabilityfaq.com/wp-content/uploads/2023/05/640px-DomainKeys_Identified_Mail_DKIM.svg_.png)
What is DKIM?
DKIM, short for Domain Keys Identified Mail, is an email authentication technology used to help…
![A hand holding picture identification, showing how an SPF record is authentication, similar to picture ID.](https://deliverabilityfaq.com/wp-content/uploads/2023/05/photo_2023-05-04_16-44-21-1024x1003.jpg)
What is SPF?
It’s not Sun Protection Factor, SPF stands for Sender Protection Framework. SPF is one of…