Exchange Server 2003 NDR #5.7.1 smtp;550 5.7.1 No such user

The user nor I can send Internet mail to user@gmail.com. You do not have permission to send to this recipient.  For assistance, contact your system administrator is returned with the NDR. Our Exchange server is not setup to deny Internet email. The person exists because the user has talked to that person and that person gave the user their email address. I checked with the user to make sure the email address was correct and they said yes. Is the error being generated from the recipients mail server, possibly due to some sort of blacklist?
cfische4Asked:
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MicrotechCommented:
have you seen if you are on a blacklist?

check out www.dnsstuff.com 

also you can try and e-mail me (address in profile) I will just let you know in the forum if I get it
cfische4Author Commented:
Thank you for your time. I did some more investigating after creating this question. I think I resolved the problem by adding an extra s into the person's name part of the email address and found that the test email didn't return. Being that unknown user was part of the error message, I felt that the email address wasn't right though our user said it was.
DarthModCommented:
PAQed with points (500) refunded

DarthMod
Community Support Moderator

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