Cannot use server's SMTP for outgoing

Migrated Exchange 2003 to a new server internal email is working fine.  Utilizing POP for outside reps.  Incoming emails are working but can't get outgoing to work when using our server as the outgoing settings (SMTP)w/authentication to use same as incoming. Login prompt keeps popping up to login again. When I setup one of the laptops at home to use comcast's smtp emails transmit fine.
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Webcc, when you say "outgoing settings (SMTP)w/authentication" I hope you're not referring to Outbound Security for SMTP because this should be set to Anonymous access so mail flow outbound can be sent from the Exchange 2003 server.

I would also check your firewall to make sure you have no ACLs blocking outbound SMTP traffic on port 25.  Make sure the public IP address the Exchange 2003 server uses to send outbound messages is not on any blacklists as well.
WebccAuthor Commented:
Sorry, I'm talking about the settings in Outlook.  Have to use the ISP's SMTP relay server instead of using the Exchange server in the SMTP entry in Outlook with the authentication setting enabled.  Has to be something with Exchange because it worked on the old server.   Thanks, Bill

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