Luca wrote:

Can I return an email back to sender with Outlook 2007, pretending
that the account doesn't exist anymore and with a returned
message?????

Not really. Mail clients can't generate non-delivery messages. That's a
server-side function. If this is for a real person whose messages you want
rejected, you can send a reply with a rule. If it's for antispam, however,
it would be pointless because spammers don't use replyable addresses or, if
they do, they belong to some innocent person whose address they've hijacked
and who wouldn't understand the rejection anyway.
--
Brian Tillman