Error code : 550-5.7.26 Your email has been blocked because the sender is unauthenticated

Products

• Email Security.cloud

Issue/Introduction

Sender domain registered in Email Security Cloud is unable to send the emails to Gmail users and receiving below error in the Track and Trace logs.

Error code:

550-5.7.26 Your email has been blocked because the sender is unauthenticated. 550-5.7.26 Gmail requires all senders to authenticate with either SPF or DKIM. 550-5.7.26 550-5.7.26 Authentication results: 550-5.7.26 DKIM = did not pass 550-5.7.26

 

Environment

Email Security.cloud

Resolution

• This error indicates that sender is not authenticating via SPF/DKIM. Please make sure that sender domain has the valid SPF,DKIM and DMARC configured. Below are the KB links that would help you to configure the same.
  • "Implement SPF records for Email Security.cloud" - https://knowledge.broadcom.com/external/article?articleNumber=161394
  • "Configuring DKIM signing for outbound mail" - https://knowledge.broadcom.com/external/article/171225/configuring-dkim-signing-for-outbound-ma.html
  • "Adding a DMARC Record" - https://knowledge.broadcom.com/external/article?articleNumber=178782#mcetoc_1gops6au31c1
• If all the above things are configured correctly then please contact the recipient's admin for the rejection reason.