Brian said:
Why? You already get a copy of every message you send in the Sent Items
folder.
Sometimes a users wants evidence that their e-mails got *sent* from the
mail server, not just that the mail server accepted their e-mail
request. That the item got moved from the Outbox to Sent Items folder
by Outlook after it received an +OK status back from the mail server
doesn't really show what the mail server did after that. However, for
auto-Bcc to be valid, the Bcc should go to a different e-mail account
than the one used to send the e-mail. E-mail providers will redirect
internal e-mails (where sender and recipient are within their own
domain) to drop them into the recipient's mailbox rather than use their
boundary mail server to send out that e-mail. By using an e-mail
account that is external to your own e-mail provider, you see that your
e-mail provider actually used their boundary host to send the e-mail (so
it got sent out rather than just relying on a redirected internal copy
sent from your account to your account which never used their boundary
host for their mail service).
I've seen lawyers ask for this a lot. While there is no guaranteed
delivery for e-mail (and the lawyers should be using registered mail
with notarized content to prove they sent it and what they sent), and
because rare few mail servers respond to delivery receipt requests, and
because recipients often disable read receipt requests in their e-mail
clients, the sender wants something to show that their mail *server*
sent out their e-mail. Seeing an item in your Sent Items folder only
means your mail server *accepted* your message, not that it sent it.