troubleshooting Question

I am getting reverse DNS Errors when sending email

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cyberleo2000Flag for United States of America asked on
11 Comments7 Solutions613 ViewsLast Modified:
When I try to send an email to I receive the follow error:

The following recipient(s) could not be reached: on 9/6/2010 2:52 PM
You do not have permission to send to this recipient. For assistance, contact your system administrator.
< #4.7.1 smtp;421 4.7.1 <>: Recipient address rejected: No reverse DNS for (c)

I am told the IP address referenced in the error is a netscreen router. My isp is microsoft exchange hosted services, they say they an't help me bcause its not their IP address. My exchange server is

Can I simply add to a reverse dns list onmy exchange server to prevent the NDRs?
Customer Engineer

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