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Re: Hotmail blackholing certain IP ranges ?

  • From: Al Iverson
  • Date: Thu Apr 26 11:02:59 2007
  • Dkim-signature: a=rsa-sha1; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:message-id:date:from:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=Fmy3VFUsoIbO3Ioe4iXsXhia7tlytubDgn2NrCutuE0sBmqHWtiLTJpufTrsU8YQiFimcK1aCgZWWj14cRn9zcfC5+AKbmIASSR7erFxjJh2wxDY396i2cbZtZ850Ea81TGW3UTg0KhSzoLCOVom/msIRVqbMrsqMT4fVK3N65c=
  • Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=qiPTPyWtgEKrb7FEpQvUHzpzlmo+eV8QLTFVZjtWCgDTiFvqYMkGATcJzk/geKN1jFQGUmn+yPQuHQjeaKQeMWqmi0rctwiWCMzVwyb6BNcCsz0kCqed4DbrJ1QKsUXRSseABIahbd5ouo2zeXjgGHulyAyljUQX6jIFTj2tHRo=

On 4/26/07, Stasiniewicz, Adam <[email protected]> wrote: 
In addition to aligning A and PTR records with the outgoing banner try the
following:

-Use the dnsstuff.com "Spam Database Lookup" tool to check the server's IP
against a ton of RBLs.  If listed, get it delisted
-Ensure that the domain you are sending from has an SPF record allowing that
server to send
-If your SMTP server support domain keys, set that up
-Ensure that the sending domain has an MX record.  This MX record should
point back to a server that will respond with a banner having a matching
domain name.  Also, it would not hurt if it had an A record pointing
somewhere (I know some email servers will do loopback checks to ensure that
the sending domain actually has a email and/or webserver).
-Check the range to see if it is on any bogon list (as we all know, some
ISPs and bogon list operators tend not to update their block lists with the
current IP assignments).
-Lastly, change the IP of the email server.  Don't move it to a new range,
just one IP over (incase it got itself on some internal hotmail blacklist).

Keep in mind...

To the best of my understanding, Hotmail isn't using any of the 200+
DNSBLs listed on DNSStuff. (And 99% of the DNSBLs listed on DNSStuff
aren't used by any major receiving sites.)

DomainKeys is not used by Hotmail.

Changing the IP address is likely to make the problem worse, not
better. A lot of this is Hotmail clamping down on IP addresses with no
history; switching to a new IP with no history starts the cycle over.

--
Al Iverson on Spam and Deliverabilty, see http://www.spamresource.com
News, stats, info, and commentary on blacklists: http://www.dnsbl.com
My personal website: http://www.aliverson.com   --   Chicago, IL, USA