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Hotmail emails to myself rejected as SPAM

  • 4 replies
  • 1 has this problem
  • 1 view
  • Last reply by inSohmniac

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Beginning around the time I updated Thunderbird to version 78.12.0, whenever I send myself an email To and From the same Hotmail account (I send myself reminders of things to do, get, etc.), it gets rejected with: _________________________________ Your message wasn't delivered because the recipient's email provider rejected it.

Diagnostic information for administrators:

Generating server: BY5PR13MB3683.namprd13.prod.outlook.com

Xxxxx@hotmail.com Remote Server returned '550 5.7.520 Message blocked because it contains content identified as spam. AS(4810)' _________________________________

This ONLY happens with this Hotmail account - I have one other Hotmail.com email account and 2 other Outlook.com email accounts - and it ONLY happens if I use Thunderbird. If I do the same thing from the Win10 MAIL app it works without issue, and if I use the Android Outlook app it also works fine.

I have quadruple-checked my account settings within Thunderbird, verified them against my other email account settings in Thunderbird, nuked the account in Thunderbird then deleted all account data left over in the Thunderbird folders for that account then rebooted and re-setup the account, and even spoken with Microsoft support and their email server admins (who claim it's not on their end, which mostly makes sense since it ONLY happens when I use Thunderbird to email myself notes). Even if I leave the message content blank and simply put "Test" in the subject line, it still gets rejected and undelivered. I'm trying to avoid nuking Thunderbird entirely if possible, because it's a pain to set it all back up with the same plug-ins and settings and et al.

I can send and receive other email from this specific account with no issues, and send email to this account from my other accounts as well as respond without issue. It's ONLY in this one account, ONLY when using Thunderbird, and ONLY when I send an email to the same account I'm sending it from. I could use my other accounts to do this but this particular account is my default email account and the one I utilize 95% of the time, so I never think to do otherwise. And until recently, it was never an issue.

Any help would be greatly appreciated, because I'm stumped. Here's the complete rejection response (with the personal tidbits removed, for security):


Delivery has failed to these recipients or groups:

Xxxx@hotmail.com Your message wasn't delivered because the recipient's email provider rejected it.

Diagnostic information for administrators:

Generating server: BY5PR13MB3683.namprd13.prod.outlook.com

Xxxx@hotmail.com Remote Server returned '550 5.7.520 Message blocked because it contains content identified as spam. AS(4810)'

Original message headers:

Received: from BY3PR13MB4849.namprd13.prod.outlook.com (2603:10b6:a03:363::18)

by BY5PR13MB3683.namprd13.prod.outlook.com (2603:10b6:a03:21a::23) with
Microsoft SMTP Server (version=TLS1_2,
cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4394.8; Wed, 4 Aug
2021 01:26:49 +0000

Received: from BY3PR13MB4849.namprd13.prod.outlook.com

([fe80::a8e5:663d:ced1:7d90]) by BY3PR13MB4849.namprd13.prod.outlook.com
([fe80::a8e5:663d:ced1:7d90%3]) with mapi id 15.20.4394.015; Wed, 4 Aug 2021
01:26:49 +0000

To: Xxxx@hotmail.com From: "My Name" <Xxxx@hotmail.com> Subject: test 2 Message-ID: <BY3PR13MB4849690CF8D52F8C4A2E93DCE5F19@BY3PR13MB4849.namprd13.prod.outlook.com> Date: Tue, 3 Aug 2021 18:26:42 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101

Thunderbird/78.12.0

Content-Type: multipart/alternative;

boundary="------------0F1E978C7E2F38EC55726380"

Content-Language: en-US X-TMN: [eo6EOEjqE5f1nuY+swUmb4lSa59LYvok] X-ClientProxiedBy: MWHPR17CA0056.namprd17.prod.outlook.com

(2603:10b6:300:93::18) To BY3PR13MB4849.namprd13.prod.outlook.com
(2603:10b6:a03:363::18)

Return-Path: Xxxx@hotmail.com X-Microsoft-Original-Message-ID: <028a923d-3c80-e1ad-37f3-3b627bb0d51e@hotmail.com> MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from [10.9.9.8] (45.43.14.96) by MWHPR17CA0056.namprd17.prod.outlook.com (2603:10b6:300:93::18) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4394.15 via Frontend Transport; Wed, 4 Aug 2021 01:26:49 +0000 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: d9553eaa-1ef3-4603-344b-08d956e6ee86 X-MS-Exchange-SLBlob-MailProps: fMOR/XCTRh0gErlYfz9tGFH7rVyjBgEpwbOC3Bz0PFOPc6Ewc/Gp85T5NuKXz206/bHsvMn3zWyr0b7cu7jeCugDeUZHKWdbBMsIMcavGNloTrkYc1jLyp9t/nUN7NN09YfoNPl3YzsAAPsGa8qJ5539bZop4F1yimau0pgdMaoXsntc452FZP/548Y/JQ8BIc6PfxoO1OeIWQRI2GAICP6j+U8O/FhiIWlGBW2UDiXLyqk3qk8NrpX/UTQEpmgLiZuxvXntJegSZCz1ozipsK+8xRJQ1uPk8MC8AgExkYs30dWquJfKK7IMmQoQJcNYOqgjd8GTsDEUDoUmsnSc81ya6wtrAyhFHrjnxvf9rb9fE2EUMvqUyBa9QlhI46Tm/Az4INJpvog1NSywMx6MVxkEYEYUuN6UECg7/vNrKh3bNL8RRFonYlSbSiKlaJG7Js4AFOapVDWdp7XTcVFpQtADQPP/csr5enXJIsC2Gj7S3uOmtTZ90LaDV8ZkmBqndCFNuG5Vm6DElCSr4l/CmMTnnPhWXM0j03bDChkeBgSyUTEcMapEcLgG02KKd2dmPTYpUDUT6LI17j+SzUL3rQ== X-MS-TrafficTypeDiagnostic: BY5PR13MB3683: X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: GtRgT4dI2/4NlyZdTeIsMTlqSn5EKAtcjMxqbbddy0Hie3WQ1GoTg1mnH84ocvNJk2xPj3YEmHQp5MWxQgTH4vJHJD6kNa+r7qzP/QOrArik+ym2AFetSMBCo5wWAcYgFFK1YcNgr73Qj4NFKR13/brlUbLaUwSn6lZlUnKW53ziy9/hIsrUuCPl32xb6xfxKhElzhewjEi31RwdwBwfNp9gnWBj1Ww7EByaHdsHoz0reL7XWHpKptRFt9xilOrw7Ub1pRw4OF7peTlb4W0lZw== X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: /r6hRaC3BW4jM3lobr5OH75tsgcXdVF8/FanRKkSgfgyKUDscwqRI6ec6aSkErnWGVoTevtfNC9uyJeUdwB25pNSQrl+wbr3Eb3dFMXR9Ex0KVaZiw/st7EAE6G39VZcH7gmlNM42ac8/zdhHsR5tQ==


Reporting-MTA: dns;BY5PR13MB3683.namprd13.prod.outlook.com Received-From-MTA: dns;BY3PR13MB4849.namprd13.prod.outlook.com Arrival-Date: Wed, 4 Aug 2021 01:26:49 +0000

Final-Recipient: rfc822;Xxxx@hotmail.com Action: failed Status: 5.7.520 Diagnostic-Code: smtp;550 5.7.520 Message blocked because it contains content identified as spam. AS(4810)


ForwardedMessage.eml Subject: test 2 From: "My Name" <Xxxx@hotmail.com> Date: 8/3/2021, 6:26 PM To: Xxxx@hotmail.com

Beginning around the time I updated Thunderbird to version 78.12.0, whenever I send myself an email To and From the same Hotmail account (I send myself reminders of things to do, get, etc.), it gets rejected with: _________________________________ Your message wasn't delivered because the recipient's email provider rejected it. Diagnostic information for administrators: Generating server: BY5PR13MB3683.namprd13.prod.outlook.com Xxxxx@hotmail.com Remote Server returned '550 5.7.520 Message blocked because it contains content identified as spam. AS(4810)' _________________________________ This ONLY happens with this Hotmail account - I have one other Hotmail.com email account and 2 other Outlook.com email accounts - and it ONLY happens if I use Thunderbird. If I do the same thing from the Win10 MAIL app it works without issue, and if I use the Android Outlook app it also works fine. I have quadruple-checked my account settings within Thunderbird, verified them against my other email account settings in Thunderbird, nuked the account in Thunderbird then deleted all account data left over in the Thunderbird folders for that account then rebooted and re-setup the account, and even spoken with Microsoft support and their email server admins (who claim it's not on their end, which mostly makes sense since it ONLY happens when I use Thunderbird to email myself notes). Even if I leave the message content blank and simply put "Test" in the subject line, it still gets rejected and undelivered. I'm trying to avoid nuking Thunderbird entirely if possible, because it's a pain to set it all back up with the same plug-ins and settings and et al. I can send and receive other email from this specific account with no issues, and send email to this account from my other accounts as well as respond without issue. It's ONLY in this one account, ONLY when using Thunderbird, and ONLY when I send an email to the same account I'm sending it from. I could use my other accounts to do this but this particular account is my default email account and the one I utilize 95% of the time, so I never think to do otherwise. And until recently, it was never an issue. Any help would be greatly appreciated, because I'm stumped. Here's the complete rejection response (with the personal tidbits removed, for security): Delivery has failed to these recipients or groups: Xxxx@hotmail.com Your message wasn't delivered because the recipient's email provider rejected it. Diagnostic information for administrators: Generating server: BY5PR13MB3683.namprd13.prod.outlook.com Xxxx@hotmail.com Remote Server returned '550 5.7.520 Message blocked because it contains content identified as spam. AS(4810)' Original message headers: Received: from BY3PR13MB4849.namprd13.prod.outlook.com (2603:10b6:a03:363::18) by BY5PR13MB3683.namprd13.prod.outlook.com (2603:10b6:a03:21a::23) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4394.8; Wed, 4 Aug 2021 01:26:49 +0000 Received: from BY3PR13MB4849.namprd13.prod.outlook.com ([fe80::a8e5:663d:ced1:7d90]) by BY3PR13MB4849.namprd13.prod.outlook.com ([fe80::a8e5:663d:ced1:7d90%3]) with mapi id 15.20.4394.015; Wed, 4 Aug 2021 01:26:49 +0000 To: Xxxx@hotmail.com From: "My Name" <Xxxx@hotmail.com> Subject: test 2 Message-ID: <BY3PR13MB4849690CF8D52F8C4A2E93DCE5F19@BY3PR13MB4849.namprd13.prod.outlook.com> Date: Tue, 3 Aug 2021 18:26:42 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.12.0 Content-Type: multipart/alternative; boundary="------------0F1E978C7E2F38EC55726380" Content-Language: en-US X-TMN: [eo6EOEjqE5f1nuY+swUmb4lSa59LYvok] X-ClientProxiedBy: MWHPR17CA0056.namprd17.prod.outlook.com (2603:10b6:300:93::18) To BY3PR13MB4849.namprd13.prod.outlook.com (2603:10b6:a03:363::18) Return-Path: Xxxx@hotmail.com X-Microsoft-Original-Message-ID: <028a923d-3c80-e1ad-37f3-3b627bb0d51e@hotmail.com> MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from [10.9.9.8] (45.43.14.96) by MWHPR17CA0056.namprd17.prod.outlook.com (2603:10b6:300:93::18) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4394.15 via Frontend Transport; Wed, 4 Aug 2021 01:26:49 +0000 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: d9553eaa-1ef3-4603-344b-08d956e6ee86 X-MS-Exchange-SLBlob-MailProps: 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 X-MS-TrafficTypeDiagnostic: BY5PR13MB3683: X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: GtRgT4dI2/4NlyZdTeIsMTlqSn5EKAtcjMxqbbddy0Hie3WQ1GoTg1mnH84ocvNJk2xPj3YEmHQp5MWxQgTH4vJHJD6kNa+r7qzP/QOrArik+ym2AFetSMBCo5wWAcYgFFK1YcNgr73Qj4NFKR13/brlUbLaUwSn6lZlUnKW53ziy9/hIsrUuCPl32xb6xfxKhElzhewjEi31RwdwBwfNp9gnWBj1Ww7EByaHdsHoz0reL7XWHpKptRFt9xilOrw7Ub1pRw4OF7peTlb4W0lZw== X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: /r6hRaC3BW4jM3lobr5OH75tsgcXdVF8/FanRKkSgfgyKUDscwqRI6ec6aSkErnWGVoTevtfNC9uyJeUdwB25pNSQrl+wbr3Eb3dFMXR9Ex0KVaZiw/st7EAE6G39VZcH7gmlNM42ac8/zdhHsR5tQ== Reporting-MTA: dns;BY5PR13MB3683.namprd13.prod.outlook.com Received-From-MTA: dns;BY3PR13MB4849.namprd13.prod.outlook.com Arrival-Date: Wed, 4 Aug 2021 01:26:49 +0000 Final-Recipient: rfc822;Xxxx@hotmail.com Action: failed Status: 5.7.520 Diagnostic-Code: smtp;550 5.7.520 Message blocked because it contains content identified as spam. AS(4810) ForwardedMessage.eml Subject: test 2 From: "My Name" <Xxxx@hotmail.com> Date: 8/3/2021, 6:26 PM To: Xxxx@hotmail.com

Modified by inSohmniac

All Replies (4)

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I fail to understand why people keep posting here when the outlook server is the one refusing your mail. Microsoft have a support forum for their mail products, I suggest you use it to ask them why they think your mail is spam. My guess is they are treating mail from and to the same email address as spam. But as there are no "rule" about what can and can not be considered spam they are free to do whatever their customers want.

more options

I get that Miscrosoft's servers are the ones rejecting the emails. But again, this ONLY happens when I use Thunderbird - it doesn't happen using Outlook or Mail or via the web portal - and it ONLY started after the last update. So what changed within Thunderbird that would make Microsoft think email to myself from Thunderbird is now SPAM, but not from any other email client/app?

more options

The information I provided in this bug https://bugzilla.mozilla.org/show_bug.cgi?id=1722916

Is this When it comes to sending mail using SMTP there is so little similarity between that and sending using web mail that success or failure is really irrelevant.

The rules applied to SMTP transmissions are not the same as those applied to web mail.

Some relevant links https://o365reports.com/2020/02/06/outlook-cant-send-and-receive-emails-blocked-as-spam/

The link suggests using https://sender.office.com/ to delist your address as a spammer. As I am unaffected I have no idea if it works. Perhaps you could try it and report your results.

Then there are threads like the following on Microsoft support, and similar can be found on just about all mail client support sites because it is an outlook.com issue, not a mail client one.

https://answers.microsoft.com/en-us/outlook_com/forum/all/remote-server-returned-550-57520-message-blocked/f4b5fd62-1c86-4591-af9c-9d70f5984abb?page=2

more options

Sadly, I have tried all these resources, to no avail.

I am stuck in a loop with Microsoft support, who all say they aren't blocking the IP's or the address, and all point back to different MS departments and/or the software, so round and round I go. Or went - I finally gave up because their techs clearly have no idea how each piece of Microsoft works or who does what.

The annoying thing is I have Thunderbird installed on 3 different computers, one with no add-ons, one with 1, and the original with 3. It doesn't matter which computer I use Thunderbird to send from or where, add-ons enabled or disabled, VPN on or off, AV on or off, different IP's, etc.. If it's from that one account TO and FROM the same address, it gets blocked as SPAM by Microsoft's servers, as if there's something hidden in the header since the latest Thunderbird upgrade that ticks the SPAM checkbox at Microsoft. But it makes even less sense because of those other Hotmail accounts setup on all 3 machines and none of them getting blocked when sending TO and FROM myself on those accounts. It's only that one address, and only using any installation of Thunderbird.

So I'm entirely at a loss. Maybe the next update will magically fix it, but I'm not holding my breath. I'm getting better at sending TO and FROM myself from the Outlook app or using one of the other Hotmail accounts in Thunderbird to send to my primary account to bypass the issue, but still, I shouldn't have to. It's very annoying that there is obviously an issue, and if there's an issue, there's a solution, but being unable to find the party that can tell me exactly where the issue is is aggravating to say the least. Even if I only knew just the cause I could probably find a solution, or at least the right people to talk to to get it resolved. But I can't even narrow that down to anything but the rejection, just not what's causing the rejection.

Anyway, thanks for the help, Matt. Should I find a solution or the issue resolves itself. I'll update this thread. But until then, it's definitely unresolved. So, if anybody else has a bit of wisdom to impart, please, impart away.