Re: Connection Filtering rejecting all emails

Peter Jones <tweeter@xxxxxxxxxxxxxx> wrote:
I've set up my fair share of Exchange boxes

You've posted this in an Exchange 2000 group for some reason....try
microsoft.public.exchange.admin for the most eyes on your posts, in the
future.


for clients of mine and
have some experience setting up Connection Filtering to use public
Blacklists. I'm running into an issue where a couple of them are
rejecting all email

All? Entirely? Including from, say, Hotmail/Yahoo? Citibank?

saying that the originator is on the Blacklist.
Both machine are SBS servers and I have gone over them to make sure
they are not set up differently than the ones I have setup and are
working.

Here is what I have set up:

Display name: Spamhaus
DNS Suffix of Provider: zen.spamhaus.org

I like them....

Customer Error Message to Return: The IP address %0 was rejected by
the Realtime Block List provider %2.

I also like to set up a custom message to return ...saying what yours does,
but appending "....if you believe this is in error, please call our office
at (main phone number)."

I have rules aslso set up for list.dsbl.org, bl.spamcop.net, and
dnsbl.njabl.org.

I wouldn't use those, myself. I use zen.spamhaus.org alone.


I made sure the public IP address and A record for the mail server

You mean, the receiving Exchange server, right?

forward and reverse to each other.

That's fine, but won't be relevant here...

I also made sure that the IP
addresses of both my and the problem machines are not on the any of
the blacklists (tested via dnsgoodies.com.)

Maybe that's not the best place to look? Always check on the blocklist
provider's website.

Here is the message I get back in the bouce (with some some small
edits):

Your message did not reach some or all of the intended recipients.

Subject: Test for Bounces
Sent: 9/15/2007 11:34 AM

The following recipient(s) could not be reached:

administrator@nopenadanoway on 9/15/2007 11:34 AM
You do not have permission to send to this recipient. For
assistance, contact your system administrator.
<mail.nopenada.com #5.7.1 smtp;550 5.7.1 $$.$$.85.2 has
been blocked by list.dsbl.org>

The message seems pretty clear to me - did you check dsbl.org ?
http://dsbl.org/main
http://dsbl.org/listing


Masking IPs/domain names makes it more difficult to troubleshoot.


Anyone experienced this that could point me in the rigth direction?

Thanks,

Peter

Bottom line, don't use RBLs maintained by the overzealous. It's better to
get spam than to reject legit business mail.

Another, easier-to-manage, option would be to use Vamsoft's ORF instead of
configuring your RBLs and other filtering in the Exchange server directly -
it's got very good logging, whitelisting, and so forth, which Exchange
alone doesn't have. You can still use the RBLs of your choice.
zen.spamhaus.org doesn't seem to generate false positives in my opinion. I
abhor spamcop.


.

Relevant Pages