Your message did not reach some or all of the intended recipients.
Subject: Insert files as printouts
Sent: 1/1/2009 12:12 PM
The following recipient(s) cannot be reached:
firstname.lastname@example.org’ on 1/1/2009 12:12 PM
503 Valid RCPT command must precede DATA
Generally, when you get this error when sending a message from microsoft outlook, it is because you did not enable authentication for outgoing emails.
To fix this error open the outlook “tools menu” and select “account settings” , from there select “Change” while selecting the account you want to use from the list. Now click the “More settings” button and select “outgoing server”, click “My outgoing server (SMTP) requires authentication” and keep “Use same settings as for my incoming mail server”
Press Ok , next , finish, close, die
try it now, it should be working.