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Old 29 Jan 2017, 06:54 PM   #16
Berenburger
The "e" in e-mail
 
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Quote:
Originally Posted by FredOnline View Post
Whilst these fine gents are helping you to sort your problem, I would point out that publishing your e-mail address(es) in the forum may make you liable to spamming.

From the information you've posted, I've found some information about you personally (looking at WHOIS, for example), that is readily available for anyone to utilise for whatever purpose.

I would suggest obfuscating your e-mail address(es) here on forum.

Also, consider enabling domain privacy with your domain registrar and putting a contact form on your web page, instead of the "remove xyz" you have opted for.
LOL. From his webpage:
Quote:
It is put in to prevent email spammers from harvesting emails on webpages.
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Old 29 Jan 2017, 11:35 PM   #17
tony17112acst
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I got a reply back from Freehostia and they asked me to send 4 messages in succession to see if greylisting was active and they replied that they are getting nothing from Comcast (which Comcast admits). So there's no greylisting.

So do I tell Comcast that DMARC is a mechanism that Freehostia checks ...for valid emails? I don't know if I understand it totally.

To me it's like comcast needing to send a technician to my brother's house to work on wiring and my brother needs to ID him (using DMARK) before letting him into the house. It's totally up to my brother whether he checks for ID (DMARC) or not, not the comcast technician. So when Comcast tells me they are not relaying my emails to Freehostia because "they need a valid DMARC record," it's like telling me that the technician didn't go into my brother's house because my brother didn't ask for ID.

Is that analogy correct, because I need to understand how DMARK works before I call Comcast back.

Thank you! I must say I am very thankful for everyone who has helped and I am stunned with the great amount of info I received here.

Berenburger, is my tonytoninixyz@hotmail.com (remove the "xyz") funny because it doesn't work? ...or something else? I'm a bit of a novice, so I'd love some input if there's a problem with it (outside of using a form). Thanks.
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Old 30 Jan 2017, 07:57 AM   #18
n5bb
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The problem you have described with the headers you posted before (sending messages from one of your personal domains to another of your personal domains) can't be due to DMARC policy failure because your DNS records for those domains don't specify any DMARC policy, and they don't provide any SPF related records either. It's harder to check the DKIM situation - I see a DKIM related DNS record for one domain but I'm not sure about the other domain. I can't tell if Comcast is DKIM signing your outgoing messages, since I don't have the complete headers of received messages which were sent by you through the Comcast outgoing SMTP servers. Here is what these terms mean:
  • SPF: Sender Policy Framework: This is a mechanism which allows owners of domains to specify which email servers are allowed to send outgoing messages with a From address at that domain.
  • DKIM: DomainKeys Identified Mail: This allows the message originator (you in this case for your domain) or a transport server (Comcast) to sign a portion of the message by adding a DKIM-Signature header. The encrypted signature allows the receiving email system to verify that the signed portions of the message were received without any changes. This is similar to taking a printed or handwritten message, placing it in a sealed envelope, signing the envelope with a signature recognized by the recipient, then sealing the message with a wax seal so that it's obvious if anyone has tampered with the envelope.
  • DMARC: Domain-based Message Authentication, Reporting and Conformance: This is a system which allows the owner of a domain to specify a policy on how SPF and DKIM are to be applied by those receiving messages from that domain.
It would be good for you to use SPF, DKIM, and DMARC for your domains in the long term. If SPF or DKIM tests by the receiver failed (which would cause DMARC to indicate a problem if both failed), then there might be a problem at the receiver. But as far as I can see, you have no SPF or DMARC policy published in the DNS records of your domains, so that can't be the cause of the current issue.

I agree with jhollington -- there is likely a block or connection problem between Comcast and the receiving ISP. It's crazy for Comcast or the receiving domain to complain about missing SPF, DKIM, or DMARC. If the mechanisms fail, then they can complain. But if they are not implemented (no DNS entries) the email should be handed off normally. The spam filters at the receiver might increase the spam score, but they shouldn't refuse to accept the messages.

As a point of reference, here are these policies for the comcast.net domain:
  • DMARC: Policy is published as "none". This means that the receiver is instructed to do nothing (not quarantine or reject messages based on SPF or DKIM failures).
  • SPF: This is hard to fully check manually, but I think their policy is "neutral".
  • DKIM: I can't check this directly, since I don't have a comcast.net account. But I assume they are using DKIM signing on outgoing messages from their domain.
Bill
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Old 30 Jan 2017, 08:08 AM   #19
jhollington
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Quote:
Originally Posted by tony17112acst View Post
To me it's like comcast needing to send a technician to my brother's house to work on wiring and my brother needs to ID him (using DMARK) before letting him into the house. It's totally up to my brother whether he checks for ID (DMARC) or not, not the comcast technician. So when Comcast tells me they are not relaying my emails to Freehostia because "they need a valid DMARC record," it's like telling me that the technician didn't go into my brother's house because my brother didn't ask for ID.
That's a pretty good analogy. There's absolutely no reason that Comcast should care whether or not Freehostia has a DMARC record when sending messages to the domain.

Quote:
Originally Posted by n5bb View Post
I agree with jhollington -- there is likely a block or connection problem between Comcast and the receiving ISP. It's crazy for Comcast or the receiving domain to complain about missing SPF, DKIM, or DMARC. If the mechanisms fail, then they can complain. But if they are not implemented (no DNS entries) the email should be handed off normally. The spam filters at the receiver might increase the spam score, but they shouldn't refuse to accept the messages.
It's even more absurd, however, for Comcast to refuse to send messages to a system simply because it doesn't have a valid DMARC record published. In fact, this is so improbable that I have to conclude that either the support person at Comcast is confused or not communicating the issue properly, or is simply blowing smoke.

Obviously, it's possible for Freehostia to refuse to accept messages if Comcast's DMARC/SPF policies were incorrectly configured, but as Bill points out, that's not the case Comcast has extremely relaxed DMARC/SPF records (to the point where there's almost no point in having them published at all). Even in this case, however, the issue would not be Freehostia's DMARC/SPF/DKIM records, but rather Comcast's.

Jesse

Last edited by jhollington : 30 Jan 2017 at 08:34 AM.
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Old 30 Jan 2017, 08:31 AM   #20
jhollington
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To help boil this down to the basic procedures of how mail transfer should work in this case....
  1. A new e-mail message is created via webmail at Comcast.net, addressed from sender@comcast.net to receiver@destination.com
  2. This message travels through the bowels of Comcast's e-mail system to an outbound SMTP server. For the sake of this discussion, let's call that outbound.comcast.net.
  3. outbound.comcast.net looks up destination.com in DNS to find the appropriate mail server. For the sake of discussion, let's say that mail server is mail.destination.com.
  4. outbound.comcast.net establishes a connection to mail.destination.com.
  5. mail.destination.com says hello, identifying itself.
  6. outbound.comcast.net says hello back, identifying itself.
  7. Assuming everything is okay, the two servers initiate an SMTP session, and outbound.comcast.net transfers the message to mail.destination.com
  8. Once mail.destination.com has received the message, the two servers disconnect, and mail.destination.com sends the message onward through the bowels of its email system to "receiver's" mailbox.
My educated guess is that the problem is occurring somewhere around steps 3 and 4. It could be happening earlier, but it definitely can't be happening after step 7, as at that point the recipient's mail server would have accepted the message, and it's no longer Comcast's problem to deal with.

Also, it's worth noting that DMARC/SPF/DKIM checks are almost never handled at the SMTP session level (steps 4-7). The only thing that "mail.destination.com" (Freehostia) could be doing on their end that would affect that is having "outbound.comcast.net" on a blacklist. In that case, the destination server (mail.destination.com) essentially "hangs up" on the sending server (outbound.comcast.net) after step 6.

However, this is assuming that Freehostia is the problem, of course, and that the problem exists at the SMTP layer. However, these are almost always permanent (500-series) failures, which would result in a non-delivery notification right away.

The real smoking gun here are the fact that these are temporary failures. There are very few reasons why a message fails with a 400-series SMTP error code, and they're almost always related to communication issues:
  • Destination not found the sender server can't find the destination domain, can't find a valid mail server for the destination domain (MX record or fallback A record), or can't find a valid address for the published mail server.
  • No answer at destination The DNS lookup succeeds and a valid IP address is returned, but nobody's home at that IP address, at least from the sender's perspective; the sending mail server "can't get there from here."
  • Bad connection to destination The connection initially succeeds, but for whatever reason the session doesn't complete. This could be the other end "hanging up" or just a quality problem with the connection itself.
Of course, in all of the cases above, these error messages would be generated internally by Comcast's servers, not anything on Freehostia's end. This may also explain the lack of an actual error code depending on how Comcast's internal systems work, the error may not be occurring at the SMTP session level at all.

While there are a handful of other common reasons why a transient error might be returned (and a whole lot of other very uncommon reasons), almost all of these other reasons would impact any sending server trying to communicate with the destination. For example, a 452 "Mailbox Full" is a common transient error, but if you were actually beyond your quota, your mailbox would be refusing messages from everybody, not just Comcast.

Jesse

Last edited by jhollington : 30 Jan 2017 at 08:42 AM.
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Old 31 Jan 2017, 08:29 AM   #21
tony17112acst
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I called Comcast today and the guy I got in tier2 said that Comcast passes all traffic to everyone and it can't be true that they are not relaying it to Freehostia (yes, even after the last guy said he observed Comcast not sending it). I pretty much lost it and asked to talk to someone else and he said he'll have his supervisor call me back ...they never called back. I will post tomorrow after I call again.
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Old 1 Feb 2017, 06:15 AM   #22
tony17112acst
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The Comcast Security Assurance Tier 2 support supervisor never called me back (or course) but I called and got the original guy that told me that Comcast is indeed not passing email traffic to Freehostia because Freehostia does not have a DMARC (or SPF/DKIM) record/policy.

When I started to explain that it wouldn't make sense that emails wouldn't be passed off because the receiver doesn't have a good spam filter (DMARC/SPF/DKIM). He didn't know why I just didn't just accept what he told me (and suggested I should stop calling them), and I told him I had 2-3 people on email forums who were experts at this advising me that this explanation didn't make sense (that Comcast refuses to send email traffic to someone who isn't filtering well enough) ...because the filtering is on the receiving end (not Comcast's sending end).

So he said "how do you know if they're more of an expert that me?" I said "I don't know, but it HAS to make sense to me and the other guys make more sense right now."

Lastly he offered the following proof that it's Freehostia's lack of a DMARC record (his words -->) When hosted with Freehostia, I didn't get the emails because there's no DMARC record and when I switched my email over to Godaddy hosting (temporarily), I now get them successfully because Godaddy is a major player and they have a DMARK policy.

BUT after we hung up I did a check on that with a DMARK lookup tool and Godaddy DOES NOT have a DMARC record for my domain despite receiving the emails normally!! (or an SPF)

Here's what I did: I told him I'd set up DMARK and if I start getting emails, I'll apologize and let him know that was the problem. So I successfully set up a DMARC record and an SPF record to boot. Guess if that got me receiving emails from Comcast? Nope.

Last edited by tony17112acst : 2 Feb 2017 at 10:40 AM.
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Old 1 Feb 2017, 06:24 AM   #23
tony17112acst
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PS - When I found a tool for DMARC lookups and that website allows the option to click on a green "Find Problems" button. When the analysis is over, it says mbox.freehostia.com is on blacklisted by UCEPROTECTL1.

See it in action here: http://mxtoolbox.com/domain/anthonytonini.com/

Could that be the the problem? Keep in mind, I cannot send SMTP email with my hosting plan at Freehostia.

Thanks!
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Old 1 Feb 2017, 09:00 AM   #24
mavas
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Question her are you able to get any emails to mail@anthonytonini.com? If so are you able to post those headers?
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Old 1 Feb 2017, 09:06 AM   #25
tony17112acst
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Sure, here's one form a gmail account:

Return-path: <csatech749@gmail.com>
Envelope-to: mail@anthonytonini.com
Delivery-date: Sat, 28 Jan 2017 19:37:37 +0000
Received: from [209.85.218.42] (helo=mail-oi0-f42.google.com)
by mail.freehostia.com with esmtps (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128)
(Exim 4.86_2 (FreeBSD))
(envelope-from <csatech749@gmail.com>)
id 1cXYoa-000ML0-4h
for mail@anthonytonini.com; Sat, 28 Jan 2017 19:37:36 +0000
Received: by mail-oi0-f42.google.com with SMTP id u143so175260723oif.3
for <mail@anthonytonini.com>; Sat, 28 Jan 2017 11:37:36 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
d=gmail.com; s=20161025;
h=mime-version:from:date:message-id:subject:to;
bh=Zsvxkh0ul2Z3qOpD3ZkYSyV0kC7+iX9YYOwBVI+Ul60=;
b=av04RFV5H5IlncHp+74+0GUFlrEicEsNZb1eOWKsKj967yXOk+avjK2Vhft01eBlKO
MhB0h0tgiSkIMmbUOpWeGMQg/TSxdqqDqy5fmDeFMj+RahJJ2rrj920qm9hHPvooK+nR
nF8IHn9E3yquMomngXqTXjN7atV+KhZ1lMAqHFa127jH38ruJLkpPFB66f/un2sZ9P6l
seOO2uwI3mnF80uD5OhC3zcXv6KRqHzEDAILAKu85yzN8uNyB7XIzzQD8DwdTGM2byMI
ikUggU5M/1GUOemIWL3D3yJJ3/LaXYLrAxK8sUaQ3OnpjS/lL0q0GgpAgvEzmOJfK0MN
COLQ==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
d=1e100.net; s=20161025;
h=x-gm-message-state:mime-version:from:date:message-id:subject:to;
bh=Zsvxkh0ul2Z3qOpD3ZkYSyV0kC7+iX9YYOwBVI+Ul60=;
b=TuwjRB00iwvxWKX6i0+uZzq78jj839LEqWjFTLukzc9q/kbGN6QysO3Qg7lvM+2iKg
PBwNQ3sSvVkCvKc9UnSajgCQ1SMrHZC/YNRtzj1Il68A/BTcasDU90QLHnOlElWUzuco
FSI8Wc4+67mMa1LJGqVOSGHpRCy30jDOwm/uMfFPa4cQUjAVEh13R2R0qt62GaT9LIeJ
AWYseAS2FBsllitdVz7ZSX5qeAp57k8UG2WnwN4gp6YSGvjOIodgh8zDJLrDAncgisBK
BJnnTIzAYA+fzl4lLhGUPHoQEQBxsFmtPfcvbA3+OD1q1lMJgbQrlO0zBkC/q5BjCtpv
FvgQ==
X-Gm-Message-State: AIkVDXIrJzVJ6hHjROHETFj5rqBXDq2v/PFsGwoeXxXMo0pC8szwV27wNapMqGoh1OgNKsK3L7bV/Cb3ac1AvQ==
X-Received: by 10.202.234.87 with SMTP id i84mr8475642oih.64.1485632255524;
Sat, 28 Jan 2017 11:37:35 -0800 (PST)
MIME-Version: 1.0
Received: by 10.157.10.168 with HTTP; Sat, 28 Jan 2017 11:37:35 -0800 (PST)
From: CSATech749 <csatech749@gmail.com>
Date: Sat, 28 Jan 2017 14:37:35 -0500
Message-ID: <CAC8t75eNE6Q_kqT5i-ewbKvoC+Vga8ruPuZee7-W7Wiufm3euw@mail.gmail.com>
Subject: Test
To: mail@anthonytonini.com
Content-Type: multipart/alternative; boundary=001a113d5d3edb856105472cb6dd
X-Spam-Score-Int: 14
X-Spam-Score: + (1.4)

--001a113d5d3edb856105472cb6dd
Content-Type: text/plain; charset=UTF-8
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Old 1 Feb 2017, 09:29 AM   #26
jhollington
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Quote:
Originally Posted by tony17112acst View Post
PS - When I found a tool for DMARC lookups and that website allows the option to click on a green "Find Problems" button. When the analysis is over, it says mbox.freehostia.com is on blacklisted by UCEPROTECTL1.
While it's theoretically possible that Comcast may not want to send to a blacklisted mail service, that still strikes me as about as odd as them caring about DMARC records when sending. Blacklists are of course normally used on the receiving end.

That said, UCEPROTECTL1 isn't a good thing, and indicates that Freehostia has been a source of spam at some point within the last seven days according to the UCEPROTECT database at http://www.uceprotect.net/en/rblcheck.php.

However, again, it seems unlikely that this is the problem, as senders don't usually care about blacklists, but who knows what Comcast might be doing.

Quote:
Keep in mind, I cannot send SMTP email with my hosting plan at Freehostia.
You mentioned this before, and it confuses me somewhat... Are you saying that your mailbox at Freehostia is receive-only mailbox? Do you not send any e-mail from there at all? Or are they webmail-only?
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Old 1 Feb 2017, 10:01 AM   #27
tony17112acst
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jholl:
With my Freehostia setup, they do not provide the SMTP service at my service level (free). I could send with their SMTP if I upgraded and paid a monthly fee. So I do use pop3 to grab all email.

Also, Wow that's good info to know ...I didn't know blacklists were for receiving!

Also, with that blacklist being only 7 days old, my problem has been since Jan 1st (4.5 weeks now), so hopefully it's not the problem.

I did let the Technician at Comcast know that Godaddy doesn't have a DMARC record and I get Comcast email there fine AND I let them know that I created valid DMARC and SPF records. He just sent me an email from his gmail account asking for headers from that suiccessful email ...so hopefully he's off the DMARC thing (which he berated me for challenging).

So they MAY be researching it right now.
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Old 1 Feb 2017, 11:24 PM   #28
jhollington
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Quote:
Originally Posted by tony17112acst View Post
With my Freehostia setup, they do not provide the SMTP service at my service level (free). I could send with their SMTP if I upgraded and paid a monthly fee. So I do use pop3 to grab all email.
Okay, I get what you're saying. They basically expect you to use your ISP's SMTP server. Do they have any webmail functionality at all?

Quote:
Also, Wow that's good info to know ...I didn't know blacklists were for receiving!
Blacklists are sometimes used for receiving email. The fact that Freehosita is on one would be a bit of a concern to me if I were a user of their service, but again if you're not sending through their SMTP services (either from a client or via webmail), it shouldn't really affect you directly.

Again, nobody should really be using blacklists to determine who to send mail to. Doesn't mean they can't do that, just that it doesn't make a lot of sense. The purpose of a blacklist is to identity which mail servers are sources of spam or other illegitimate messages, which (like DMARC and SPF) would only be relevant for receiving messages from those servers.

Quote:
Also, with that blacklist being only 7 days old, my problem has been since Jan 1st (4.5 weeks now), so hopefully it's not the problem.
Well, 7 days is the normal expiry range if no "bad" activity is detected within 7 days, it's cleared off. It's not impossible that this window gets extended if there's a recurring problem.

Quote:
I did let the Technician at Comcast know that Godaddy doesn't have a DMARC record and I get Comcast email there fine AND I let them know that I created valid DMARC and SPF records. He just sent me an email from his gmail account asking for headers from that suiccessful email ...so hopefully he's off the DMARC thing (which he berated me for challenging).
Well, that's at least more useful progress that suggests they're looking into it instead of just dishing out canned responses that sound like they're just trying to get rid of you.

Again, it's not impossible for Comcast to be looking at DMARC records or blacklists when sending. IMHO, it would be pretty silly of them to do so, but it wouldn't be out of the question especially in the case of blacklists; the lack of a DMARC record doesn't say the mail system is "bad" whereas a blacklist entry definitely is a red flag that something is wrong.
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Old 2 Feb 2017, 02:29 AM   #29
mavas
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Quote:
Originally Posted by tony17112acst View Post
by mail.freehostia.com with esmtps (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128)
This might be the cause. When you do a MX lookup for your domain you get mbox.freehostia.com

Try updating the mx record to point to mail.freehostia.com instead of the mxbox.freehostia.com
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Old 2 Feb 2017, 03:01 AM   #30
tony17112acst
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mavas: I'll have to digest that recommendation (since I am a novice), but will your recommendation explain why I get email from everyone else in the world ...but not comcast? FYI, when you setup the account, we are instructed to use mbox.freehostia.com.

Jholl: Yes, they have webmail ...it's what I'm using temporarily.
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