that's your mail server kicking it back, not outlook or the junk filter.
since it fails then works on a second try, it sounds like authentication --
go into Outlook's tools, email accounts, change existing and open the
account's properties. Open More settings, outgoing server tab and look for
the check box to authenticate when sending. Select the one for using the
incoming password.

Signature
Diane Poremsky [MVP - Outlook]
Author, Teach Yourself Outlook 2003 in 24 Hours
Coauthor, OneNote 2003 for Windows (Visual QuickStart Guide)
Outlook Tips: http://www.outlook-tips.net/
Outlook & Exchange Solutions Center: http://www.slipstick.com
> Outlook 2003 - When I reply to an email, unless I
> physically add them to acceptable senders/receivers the
[quoted text clipped - 3 lines]
> accepted. I turned off the junk mail filter and it still
> does it. AHHHHHHHHHHH