1. We need a Outlook(2000 and 2002) add-on
2. End users use outlook to send emails, they write drafts in offline status, and when they try to send mail, the add-on check a xml file, which is the white list of all email address allowed.
3. if the recipient is in the white list, then put the mail in outbox
4. if not, redirect the mail to folder “Unauthorized mails” (addon will create this folder if not existed)
xml file should be encrypted so that end user cannot directly edit it.
Xml file should be able to contain 2 kinds of filters, the first is specific address, such as ABC@hotmail.com, the other one is domain address, such as hotmail.com