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I have installed DKIM-Filter on Postfix after reading this tutorial

My email now has a DKIM signature but still it is landing in the SPAM folder. Here is the header

    Received-SPF: neutral ( is neither permitted nor denied by best guess record for domain of client-ip=;
Authentication-Results:; spf=neutral ( is neither permitted nor denied by best guess record for domain of; dkim=hardfail (test mode)
Received: from (localhost [])
    by (Postfix) with ESMTPA id 34858530E8
    for <>; Mon, 28 Feb 2011 12:23:07 +0530 (IST)
DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple;; s=mail;
    t=1298875987; bh=bo+H1VYPIHMja2u7i1lnzr4k/j4Pe8iSf79bVw94XpI=;
     Content-Type:Content-Transfer-Encoding; b=nhTdlnUwo0iUJ92ycQzKSRjw

Also my mail.err file shows

Feb 28 12:17:03 ivineet dkim-filter[32181]: 1F788530E1: no signature data
Feb 28 12:18:02 ivineet dkim-filter[32181]: 432BA530E2: no signature data

How to fix it

share|improve this question
Check that your dns txt records exist – topdog Mar 3 '11 at 15:44
up vote 2 down vote accepted

Look at the line above the "no signature data", is says something like this:

Jul  4 10:33:46 pa04 dkim-filter[29984]: 9A95B340F6C external host localhost.localdomain attempted to send as
Jul  4 10:33:46 pa04 dkim-filter[29984]: 9A95B340F6C: no signature data

If so, create file /etc/postfix/dkim/hosts with list of hosts who's email to sign and add to the /etc/dkim-filter.conf the following lines:

ExternalIgnoreList      /etc/postfix/dkim/hosts
InternalHosts           /etc/postfix/dkim/hosts
share|improve this answer

What is the value of "Domain" in your dkim-filter.conf? I experienced the same problem when stating the actual domain, and it was fixed by rather using a wildcard.

from 'Domain' to 'Domain *', leaving selector and KeyFile intact.

Hope it helps.

share|improve this answer
+1 Simpler solution. – kubanczyk Nov 19 '15 at 9:53

Here is answer click : a=rsa-sha256 => a=rsa

And you dont have spf record: bind9:          IN      TXT "v=spf1 a mx -all"

or          IN      SPF "v=spf1 a mx -all"

this means deny all mail without A record fro MX entry (something like this)

share|improve this answer
rsa-sha256 seem to work for me. – 3molo Apr 7 '11 at 8:15
and this doenst work for me with yahoo or google. i used rsa-sha1 rsa-sha256 – MealstroM Apr 7 '11 at 8:40

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