Set your SMTP server configuration settings to use authentication and try
again.
Robert Sparnaaij [MVP-Outlook]
Coauthor, Configuring Microsoft Outlook 2003
http://www.howto-outlook.com/
Outlook FAQ, HowTo, Downloads, Add-Ins and more
http://www.msoutlook.info/
Real World Questions, Real World Answers
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"RochelleW" <RochelleW@discussions.microsoft.com> wrote in message
news:C1E65991-6178-4137-B71A-850DA9DD4C25@microsoft.com...
> I have just started using Outlook. I have attempted to send emails to
> addresses that I know are valid and keep getting a System Administrator
> message saying
> 553 sorry, that domain isn't in my list of allowed rcpthosts (#5.7.1)
>
> Can anyone tell me what to do about this? It doesn't seem to matter what
> email address I am using. And I have tried several.
>