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Exchange question

Hi there

I have a customer who is running a exchange server, But some emails he sends are blocked by some outside email servers, eg sorbs, He has contacted people at sorbs and they say its not there problem, But this problem also has problems with ISP email servers as well.
He has tried changing his Ip address with his ISP, and it still happens. he is running a .com in New Zealand, would this have anything to do with it?
Is there anyway I can redirect a email  through a ISP proxy server??

Any ideas please post :)

1 Solution
Lee W, MVPTechnology and Business Process AdvisorCommented:
Is his SMTP server's IP static or Dynamic?
milltechtgaAuthor Commented:
The SMTP is Static.. also to note it doesnt get banned if an email is set directly to a ISP or email addresses like hotmail etc.. just private email servers using firewalls like cbl.abuseat.org
Chris SlackIT ConsultantCommented:
This just happened to me. When email were sent to 1 .com company the were rejected. It turn's out the ISP had to clear the cache on the smtp server. Once they did that it worked fine. Problem is trying to get the ISP to clear there cache!

Good Luck!
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This could be a due to a SPAM block list. I've seen similar issues where an IP range (that includes your SMTP address) for the ISP gets added to a block list. As a result certain domains refuse to accept mail from your SMTP server. We had to contact the ISP and have them get their IP range removed from the list. On other occasions we were able to apply directly the the block list admins to have our IP address removed. You should be able to search the list and find if you are on it.

You can enter your IP at http://www.robtex.com/rbls.html and it will check multiple blacklists and let you know if your address is listed anywhere for blocking.
milltechtgaAuthor Commented:
Thanks man that list is an awesome site and so helpful :)
Thanks, and good luck.
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