Using the XQ Secure Gmail extension, you can revoke access to previously sent messages. Revoking a message makes it unrecoverable for you and all recipients.
- Open your Sent Mail folder and select the email you would like to revoke access to.
- On the email message, click on the icon on the top right and then on Revoke Now. The message will no longer be available to anyone.
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You can also revoke access from the Dashboard to all or some recipients.