With SendBoard, you can add an email address that will be BCC'd on every outbound email. This is useful for when you need to keep a copy of all sent emails in an email inbox, outside of SendBoard.
You can set an outbound bcc address in the mailbox settings under Advanced Settings.
If your outbound BCC address is the same as your custom address
Having an outbound bcc address that is also your custom address can cause SendBoard to create duplicate cards. If this is happening, check that your forwarding rules don't forward emails that come from your custom address.