In order for email This configuration is optional and is not directly related to ClosePlan or People.ai.
Salesforce often sends emails on behalf of users, such as email alert workflows or custom Apex initiated notifications. This also applies to all email notifications sent by the ClosePlan application.
In order to avoid security alerts or even refusal of emails sent through SFDC on behalf of any user, company needs to configure such emails, proper SPF DNS records .This configuration is not related to ClosePlan or People.ai, the customer is responsible and it should be actually in place already, because its likely that customer’s SFDC org is sending email on behalf of usersconfigured in your DNS settings.
To setup SPF records, please follow the steps in the this official Salesforce article:
https://help.salesforce.com/articleView?id=000315520
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