POP Retrieval and SPF/DKIM verification

Discussions on webmail and the Professional version.
Post Reply
u985
Posts: 3
Joined: Mon May 22, 2017 9:33 am

POP Retrieval and SPF/DKIM verification

Post by u985 »

I receive all email messages through POP Retrieval.
In such a case, are incoming messages tested with SPF and DKIM?
If not, how to configure MailEnable Professional to be verified this way?

dbly
Posts: 54
Joined: Wed Aug 20, 2008 9:18 pm

Re: POP Retrieval and SPF/DKIM verification

Post by dbly »

Incoming email messages, whether they are sent from you via your mail client or from outside parties and addressed to you, are all received via SMTP. That is where you configure SPF checking.

DKIM is inserted by Mailenable if you have gone to through the additional steps to configure it, but it is not checked on incoming mail by default. To do that you need to implement SpamAssassin integration and set up the checking there.

It doesn't matter whether you retrieve your email via POP, IMAP, or Webmail - those checks are completed before the mail ever gets to that point.

u985
Posts: 3
Joined: Mon May 22, 2017 9:33 am

Re: POP Retrieval and SPF/DKIM verification

Post by u985 »

dbly wrote:Incoming email messages, whether they are sent from you via your mail client or from outside parties and addressed to you, are all received via SMTP. That is where you configure SPF checking.
Perhaps I did not express myself precisely.
My MailEnable server receives messages from the internet only from external mailboxes through the "POP Retrieval" function.
All incoming messages land in the inboud queue of the POP connector.
Are such messages also verified by the SPF?
If not, is it possible to configure the server so that these messages are verified?
dbly wrote:DKIM is inserted by Mailenable if you have gone to through the additional steps to configure it, but it is not checked on incoming mail by default. To do that you need to implement SpamAssassin integration and set up the checking there.
In the Filters, there is a standard criterion "Where the message DKIM verification return results matching".
When does this feature work?
For all received messages?
Only for those received through SMTP?
Only if you enable some settings? What settings?
Only if you use external addons (such as SpamAssassin)?

dbly
Posts: 54
Joined: Wed Aug 20, 2008 9:18 pm

Re: POP Retrieval and SPF/DKIM verification

Post by dbly »

I actually forgot about that filter - I don't use it and do all of my DKIM checking in SpamAssassin. Filtering is run on mail retrieved using POP Retrieval, so that filter should work just fine for your needs.

SPF, however, is based upon the IP address of the delivering mail server. Mailenable may not have that information when the message is coming in via POP Retrieval since it didn't accept the message. Even with Spam Assassin I'm not sure that SPF checking would work out of the box because Mailenable would prefix the headers with the POP Retrieval header, and that would probably throw off the default rules. A custom spamassassin rule would probably have to be written to compensate.

Mailenable normally adds a header called "Received-SPF", however that is probably inserted by the SMTP connector. If you look at your message headers and it is there then it is working in your configuration. If not, you might have to do a bit of testing.

Create a new filter, select the criteria, and as action insert a header. ie:

Filter Name: DKIM-FAIL
Criteria: Where the message DKIM verfication results matching : FAIL
Action: Add a header to a message : X-ME-DKIM = FAIL

Add similar rules for DKIM Pass and DKIM Intermediate, and SPF (Fail,Pass, Soft Fail, Error, Neutral, and None).

Then, after you pull mail using the POP Retrieval you can look at the message headers in your mail client and you can see exactly what MailEnable is seeing at the time of filter execution. Once you know, you can then modify the filters to take other actions - such as mark the message as spam.

u985
Posts: 3
Joined: Mon May 22, 2017 9:33 am

Re: POP Retrieval and SPF/DKIM verification

Post by u985 »

dbly wrote:If not, you might have to do a bit of testing.

Create a new filter, select the criteria, and as action insert a header. ie:

Filter Name: DKIM-FAIL
Criteria: Where the message DKIM verfication results matching : FAIL
Action: Add a header to a message : X-ME-DKIM = FAIL

Add similar rules for DKIM Pass and DKIM Intermediate, and SPF (Fail,Pass, Soft Fail, Error, Neutral, and None).
I did such tests (SPF verification enabled on SMTP Connector).
DKIM verification result is always "indeterminate".
No SPF header has been added (I added a filter for every status).
The same message sent to gmail is verified there (both DKIM and SPF have status PASS).
It looks like neither of these verification methods work for POP Retrieval in the MailEnable.

Post Reply