With the Summer '22 release, Salesforce blocks users with unverified emails in Free or Trial organizations from sending emails until they verify their email address, reset their password, or complete identity verification. This article explains why the INSUFFICIENT_ACCESS error appears when sending email and how to resolve it.
Salesforce requires email verification to prevent unauthorized email sending and protect org security. If your email address isn't verified, you may see this error when trying to send email from within Salesforce.
Users in a Free or Trial organization who try to send an email after composing it will see an error similar to "INSUFFICIENT_ACCESS: insufficient access rights on cross-reference id: 005XXXXXXXXXXXX" — the number is the valid Salesforce User record ID of the sender. However, no error message is displayed when sending an email from a Case record.
This error can also appear when a System Administrator uses "Login As" for an unverified user in any organization and tries to send email from Salesforce as that user.
If you receive this error, verify and authenticate your email address by following the steps in the linked article below in Additional Resources. Once your email address is verified, you'll be able to send email normally.
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