the server the person you are sending to is blocking your mail for one
reason or another. You can't do anything, except use a different SMTP
server.

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Diane Poremsky [MVP - Outlook]
Author, Teach Yourself Outlook 2003 in 24 Hours
Coauthor, OneNote 2003 for Windows (Visual QuickStart Guide)
Author, Google and Other Search Engines (Visual QuickStart Guide)
Outlook Tips: http://www.outlook-tips.net/
Outlook & Exchange Solutions Center: http://www.slipstick.com
> At random receive a message when replying to a received
> email"553 sorry, that domain isn't in my list of allowed
> rcpthosts(#5.7.1)
> How do I overcome this problem?