Error message: The email address must be unique within the organization

When creating a new user, it is possible you receive the following message if the user already exists in the account:

In the example above, we cannot save Sal as a user because he already exists. His account has simply been deactivated. When users are deactivated, all their data remains in the account (though they can no longer log in or be reviewed anymore).

See our article on reactivating users to resolve this.