You are required to select a denial reason whenever a customer attempts to create an account online and you opt to deny the request. You can modify the available denial reasons or create your own.
Go to Administration > Population Settings > Denial Reasons.
Choose one of the following:
To create a new denial reason, click Add New.
To modify an existing denial reason, click the Description of the reason that you want to modify.
Enter a brief Description of the denial reason.
Enter the Text to include in the email to customers whose account requests have been denied for this reason.
Click Save.
Approving or denying a pending customer account request
Adding or modifying an account creation question