We recently had a customer get a bounce-back from Spamhaus, it complained that he had sent the email without SMTP Authentication. Now, setting this up on a standard POP3 mailbox in Outlook is no problem, the issues start when we have to set it up using Exchange.
They currently have a root@ POP3 account being received by the server which then gets distributed accordingly.
How do we turn on SMTP Authentication for all emails going out from the server?
Server OS: SBS 2003
Exchange: Exchange 2003 SP2