Top Deliverability’s Blog
Spam Resource: Gmail now rejecting unauthenticated mail
- September 18, 2023
- Posted by: Top Deliverability
- Category: Industry News Spam Resource
Al Iverson just issued another engaging article on Spam Resource:
Gmail has long pushed for adoption of email authentication best practices from email senders, effectively making it tough to get to the inbox without proper email authentication in place. They also, for years now, have been very cautious about what mail they accept over IPv6, declining to accept mail over IPv6 that fails authentication checks. Well, now those same checks now apply to all mail sent to Gmail — over IPv4 or IPv6. Meaning, if you want to send mail to Gmail, you need to authenticate that mail with Domain Keys Identified Mail (DKIM) or Sender Policy Framework (SPF).If you’re trying to send mail to Gmail subscribers, and the mail doesn’t authenticate properly, it’ll be rejected with this error message:550-5.7.26 This mail is unauthenticated, which poses a security risk to the sender and Gmail users, and has been blocked. The sender must authenticate with at least one of SPF or
Continued here: Gmail now rejecting unauthenticated mail
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- Glossary: Authentication
- Glossary: DomainKeys Identified Mail (DKIM)
- Glossary: Sender Policy Framework (SPF)
- Glossary: Sender
- Glossary: Email Service Provider (ESP)
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