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![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(281.6, 43%, 37%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EK%3C/text%3E%3C/svg%3E)
I am at my wits end. We have a Exchange 2016 installation (CU21) runningo n a Server 2016 VM.
For most intents it's works fine for our company, however there is one small hiccup, and my supervisor refuses to let it drop.
Our phone system (FreePBX/Asterisk) Is setup so that after hours, requests for tech support are sent to a distribution group on the Exchange server. This message is sent each time without fail, and we have never had a problem with it. This distribution list then is supposed to forward this message to the technicians cells phones and such. One of our techs is on T-Mobile, and receives these messages just fine. The other techs are on Verizon and never seem to get the messages.
The messages are text and attached VM. We have verified the emails being sent to are the ones for external email to text message addresses. When we try and test this, we can send messages from email to them singly, but for some reason when it's in this group, it fails every time. My boss has had me chasing this for 2 months now, and I cannot seem to find issue other than something on Verizons end must not like messages with BCC or CC in them.
I can find no issues with the settings. All our other distro group emails work ok, this is the only one that fails. We have tried re-creating it with the same result.
Any suggestions?
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(25.6, 67%, 12%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EJS%3C/text%3E%3C/svg%3E)
Hi @KevinL
Could you please provide more information about your environment? Is your phone system a 3rd party system with a mailbox or just as a relay? How does it integrate with your Exchange server?
In addition, does your distribution group only have internal users? And please also tell more about the 'SMS message' you mentioned below, is it similar to push notification?
And as you introduced above, users using T-Mobile can always receive the messages fine while Verizons not, I would consider it may also related to the configuration for Verizons, you could also try contacting for Verizons to get further support to check if anything missed. Thanks for your understanding!
The phone system is a dedicated VoIP server that interfaces to a secure phone network for phone operation, and to our normal internal network for administarative functions.
The Exchange server is is internally hosted, on the internal network.
The phone system, upon someone leaving a VM in the after-hours support mailbox sends an email with the WAV file attached to the Exchange server on the internal network.
The DL is comprised of all internal users, and it's members are the internal emails of the technicians, and their cell phone numbers. The major phone carriers provide SMTP addresses that mail can be sent to to be sent to the end phone via multi-media SMS. (ie <phonenumber>@tmomail.net for t-mobile)
If we manually from an internal account send a message to a single Verizon endpoint it works, but when we try and send to multiple endpoints (like the DL does) it fails. We are currently testing if an purely external email address will receive the email ok, or if it too fails.
Hi @KevinL
Thanks for providing more information. Have you contacted with Verizons to confirm this?
spf=neutral (google.com: 72.43.74.25 is neither permitted nor denied by best guess record for domain of asterisk@phones.microworx.com) smtp.mailfrom=asterisk@phones.microworx.com;
dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=microworx.com
Could be failing SPF when sent to the DL from that phone system.
Can you add a regular external email address to that DL and see if it gets delivered or check the headers of the one that works for T-Mobile?
There are normal emails in the list as well, internal addresses, and they receive the notifications without issue. I can add an external and test, but IIRC, they work. Not sure how to check the headers for a multimedia SMS message, which is how the end user receives it on their phone.
Yea, can you get the headers from an external email that you test with adding to that DL? Would love to see if its failing SPF or DMARC.
We have finally completed an external mail test.
The test passed, and the email with attachment came through to thier email within about 30 seconds of leaving the test message.
Here si the 'original message' as gmail presented it with headers
Delivered-To: <withheld>@Stuff .com
Received: by 2002:adf:fb09:0:0:0:0:0 with SMTP id c9csp1418712wrr;
Wed, 17 Nov 2021 12:17:59 -0800 (PST)
X-Google-Smtp-Source: ABdhPJzguDLlGw+GGvHCmOgmCeSUp0xM4E2jOVJ8Fv3Y3RlAoGzGmBcNzSrnaMsdiQ+iNcqHIo2+
X-Received: by 2002:a05:6638:1382:: with SMTP id w2mr15671616jad.50.1637180278868;
Wed, 17 Nov 2021 12:17:58 -0800 (PST)
ARC-Seal: i=1; a=rsa-sha256; t=1637180278; cv=none;
d=google.com; s=arc-20160816;
b=NOD11AbKQ7OdThcwTzlYzTKca/BX/NIN8dCGOIvqpjqilj27a6+FBd7KZ+ZjCqLsQN
ZSt9h8PXwGdiL0hUWY1KxiKUQS+2xKxQ7oaXtSpdrzPsnayaplAjOAzZRBkCWIYjHwYE
ND/2iF487t+qOM5uX/JhnAuahbhaBIheBFNEvtys0AH44yfrvrEXWUnZyy/aGhz5yWq1
SCmv7Ah3Hu8SSCmA04CQNOoFL6ZqoV+bX+KwYLJxKexrr6UbyBRmnSwCT9VCa78o5EZ5
aC55pd3zN4Da0CjC269iimdclXaoA69WTovypVhE8QlUrhDD85z7E4IWb5DOH/JABzo/
P7xQ==
ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816;
h=mime-version:message-id:subject:to:from:date;
bh=DHw/vB282t4X3dJKNBiVQkONp6InJ3U0QcqT96Rexn0=;
b=nHh2jAjL7iA3Z9poKfzp3XaX6WlTK3UDwYd8LQiZszBPU754jki2WpCmgmAYMNRQh2
Nt2GPnwk7nzHaIT2zRZkSBTI841E7BWvr5S1GtM5Bx1vS3BEjvFsjmDTLtTIVB0FwQSU
/xOxXohpCZkEpo54Z6BhdtdmIMbcnnRHSoPDRsc31TxZXc1tQTM6AwjbR+FqAWwDl3xx
QdFSKCNCb83tAi/Wl6qXQcMiphxaRCn8Y+j0yQsDZlZ7SPyeVAI9OSZ+9FS8eXczjev5
1xkwa2hJgYmX9riiLpjaX7MABxgY4bD5XPj9cjEXI3l4hpzzrTgUbfC9X0D2b95WyzXY
NgEQ==
ARC-Authentication-Results: i=1; mx.google.com;
spf=neutral (google.com: 72.43.74.25 is neither permitted nor denied by best guess record for domain of asterisk@phones.microworx.com) smtp.mailfrom=asterisk@phones.microworx.com;
dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=microworx.com
Return-Path: <asterisk@phones.microworx.com>
Received: from EXCHANGE2K16.office.microworx.com ([72.43.74.25])
by mx.google.com with ESMTPS id f14si2059398ila.81.2021.11.17.12.17.58
for <<WITHHELD>@Stuff .com>
(version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128);
Wed, 17 Nov 2021 12:17:58 -0800 (PST)
Received-SPF: neutral (google.com: 72.43.74.25 is neither permitted nor denied by best guess record for domain of asterisk@phones.microworx.com) client-ip=72.43.74.25;
Authentication-Results: mx.google.com;
spf=neutral (google.com: 72.43.74.25 is neither permitted nor denied by best guess record for domain of asterisk@phones.microworx.com) smtp.mailfrom=asterisk@phones.microworx.com;
dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=microworx.com
Received: from EXCHANGE2K16.office.microworx.com (192.168.0.4) by EXCHANGE2k16.office.microworx.com (192.168.0.4) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.15; Wed, 17 Nov 2021 15:17:22 -0500
Received: from MWX-Phones (192.168.0.9) by EXCHANGE2K16.office.microworx.com (192.168.0.4) with Microsoft SMTP Server id 15.1.2308.15 via Frontend Transport; Wed, 17 Nov 2021 15:17:22 -0500
Received: by MWX-Phones (Postfix, from userid 995) id 2F0FB813665D; Wed, 17 Nov 2021 15:17:57 -0500 (EST)
Date: Wed, 17 Nov 2021 15:17:57 -0500
From: FreePBX Phone System <rob@microworx.com>
To: Emergency Voicemail <techoncall@microworx.com>
Subject: FreePBX Voicemail Notification
Message-ID: <Asterisk-7-1490993192-500-2677@VOIP01.OFFICE.microworx.com>
X-Asterisk-CallerID: 105
X-Asterisk-CallerIDName: 105-Kevin
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="----voicemail_750026771517083761"
Return-Path: asterisk@phones.microworx.com
X-Auto-Response-Suppress: DR, OOF, AutoReply
------voicemail_750026771517083761
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 8bit
Emergency Voicemail,
There is a new voicemail in mailbox 500:
From: "105-Kevin" <105>
Length: 0:07 seconds
Date: Wednesday, November 17, 2021 at 03:17:57 PM
Dial *98 to access your voicemail by phone.
Visit http://AMPWEBADDRESS/ucp to check your voicemail with a web browser.
------voicemail_750026771517083761
Content-Type: audio/x-wav; name="msg0006.wav"
Content-Transfer-Encoding: base64
Content-Description: Voicemail sound attachment.
Content-Disposition: attachment; filename="msg0006.wav"
------voicemail_750026771517083761--
here is your issue as suspected
spf=neutral (google.com: 72.43.74.25 is neither permitted nor denied by best guess record for domain of asterisk@phones.microworx.com) smtp.mailfrom=asterisk@phones.microworx.com;
dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=microworx.com
The FROM domain doesnt have am SPF record:
phones.microworx.com
Verizon is probably dropping those based on that.