Question : Can not deliver the message I sent?

I have windows 2003 and Exchange 2003 I can send to every one but
Whin I sent any Email from my Company (*)@zamilofshore.com to [email protected] or alexey.sidorenko@tts-consult.com its bonce back to me
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Can not deliver the message you sent. Will not retry.

Sender:

The following addresses had delivery problems
     Reply from mail.wildpark.net[217.77.208.132]: 554 5.7.1 : Relay access denied
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But for the same recipient from G-mail or Yahoo-mail  its OK.
What is the problem an how to solve

Answer : Can not deliver the message I sent?

You're ISP is also listed at UCEProtect: http://www.uceprotect.net/en/rblcheck.php?ipr=212.93.195.116