DKIM provides a way for validating a domain call identification that is associated with a message through cryptographic authentication. The identification is impartial of other electronic mail identities, along with the writer’s From: Subject.
You can follow below steps to create DKIM.
Open Google Reseller account or admin account
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Click on the Admin Console
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After opening admin console, you can go to Apps> Google Workspace> Gmail
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You will see an option Authenticate email click on that
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Authentication email page is open select your domain for which you can’t to create DKIM and click on generate.
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After that click Generate new record you will see the notification in bottom center of screen that DKIM Authenticated successfully…Thanks 😊