"550 5.7.1 <email@example.com>...Relaying denied. IP name lookup failed" Error in Exchange 2003
Posted on 2006-04-07
I have searched the web and tried about every solution I could find, but none of them fixed the relaying problem I have.
I am a college student, in addition to working in the IT department at my company. I want to use IMAP to login to my school account and send/receive emails. I'm able to receive them fine, but when I try to send to anyone I get the message above. If I reply to a message I received on that account I usually don't have a problem.
Steps taken so far:
Added MX record to Exchange server in DNS forward lookup zone.
All other steps were reverted back to original settings when I discovered that they did not work.
We are using a Check Point SmartCenter server as our firewall.
If I try to resend the message, using Outlook's "Resend this Message" under the Actions menu, using my Exchange account to send and modifying the From to be my school email address I get a different error message:
The following recipient(s) could not be reached:
firstname.lastname@example.org on 4/7/2006 10:10 AM
You do not have permission to send to this recipient. For assistance, contact your system administrator.
If I use my Hotmail account to send from I can change the From field and the message goes through fine.
RPC over HTTP is enabled, so of course I am using Outlook 2003. This occurs whether I am at home on my laptop or logged in directly at work. When I am on campus it happens less frequently, sometimes not at all.