This blog can help you to understand the default WHMCS Email settings when users create accounts.
Notification Type | Users | Admin |
Email Verification | Yes | Bcc |
Welcome Email | Yes | Bcc |
Customer Invoice | Yes | Bcc |
New Order Notification | No | Yes |
Order confirmation | Yes | Bcc |
Payment confirmation | Yes | Bcc |
New Account Setup | Yes | Bcc |
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