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Invite the user utilizing the same steps you would for any other user, as described in the Add Users section of this article.
You will see a notification that the user has an existing PreVeil account and that they will be invited to join your organization. Click on the Invite button.
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For the User:
The user will receive the invitation email in their PreVeil inbox. Click on the View invitation to join button.
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Click on the Join This Organization button.
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The user’s account will now be subsumed into the PreVeil organization.