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Cannot receive emails

  • 3 replies
  • 1 has this problem
  • 1 view
  • Last reply by Matt

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Hello all, I hope this message finds you well. I am wondering if somebody could please help me with the following. Recently, I have been unable to receive replies to my business emails. When a client tries to reply to my mail, the mail will not send and instead gives the following spam error:

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

Initially, I tried removing my signature links from my emails. This seemed to help a bit, up until a client tried to send a fresh email (as opposed to a reply) and found that my email name (a .com email address I have had for over a decade) was rejected.

I am not tech savvy and cannot discern who the email is being rejected by (is it Thunderbird?). If anyone supplies an answer, could they please take care to explain steps in lay user terms.

Thank you.

Hello all, I hope this message finds you well. I am wondering if somebody could please help me with the following. Recently, I have been unable to receive replies to my business emails. When a client tries to reply to my mail, the mail will not send and instead gives the following spam error: Remote Server returned '550 5.7.520 Message blocked because it contains content identified as spam. AS(4810)' Initially, I tried removing my signature links from my emails. This seemed to help a bit, up until a client tried to send a fresh email (as opposed to a reply) and found that my email name (a .com email address I have had for over a decade) was rejected. I am not tech savvy and cannot discern who the email is being rejected by (is it Thunderbird?). If anyone supplies an answer, could they please take care to explain steps in lay user terms. Thank you.

All Replies (3)

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Does your initial email contain content pasted into Thunderbird from Microsoft office?

Just to be clear this is not Thunderbird. The remote server should be identified by name, but is usually the server for the person that clicked reply to your email.

They got your email and can not reply you say, so this really has nothing to to do with you or your mail setup and everything to do with the person you emailed and their mail setup. But if you are pasting from Microsoft office I have seen such content trigger spam tools on some servers.

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Hi Matt, thank you for taking the time to help me with this. I don't think I used any cut and paste from Microsoft but instead, typed the signature into a blank email, then saved this email as an html signature file. I will however start over just in case my memory is mistaken. Thank you so much for the tip, will see if this helps. A client was also kind enough to send me a full data report, will paste some of the data below (ip data removed). It supports what you are saying about where the error is occuring.

Unfortunately, I cannot mark this thread as resolved just yet as, after making a fresh signature, it may take some time to see how much more mail is rejected (seems to be sporadic).

Thanks again.

Received: from .prod.protection.outlook.com

 by .prod.protection.outlook.com with Microsoft SMTP Server 

Received: from .prod.exchangelabs.com

 by .mail.protection.outlook.com
 with Microsoft SMTP Server 

X-IncomingTopHeaderMarker: OriginalChecksum:CC38E919FACE1F29AC6754909A7ACA5F20C4FBEBB1C76C84BDD1A19235219563;UpperCasedChecksum:247053077DA40F913E4BD1DE8BFF509960ECEAB348FE48C20B3BE4D82FE26402;SizeAsReceived:6817;Count:44 Received: from AM6PR01MB549.eurprd01.prod.exchangelabs.com

Content-Type: application/ms-tnef; name="winmail.dat" Content-Transfer-Encoding: binary X-MS-Has-Attach: X-MS-TNEF-Correlator: <.eurprd01.prod.exchangelabs.com> MIME-Version: 1.0 X-TMN: [SeFVqdZBLlK1EDv050NyqNYnp/cvs0sZ] X-MS-PublicTrafficType: Email X-IncomingHeaderCount: 44

X-EOPAttributedMessage: 0 X-MS-Office365-Filtering-Correlation-Id: f0aa90bb-b9e0-4ef3-bb35-08d94295a47e X-MS-TrafficTypeDiagnostic: DB8EUR06HT019: X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info:

Modified by nathan47

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Just a suggestion. Get your correspondent to reconfigure their outlook copy to not send rich email. All that stuff is about an attachment winmail.dat and that is created when outlook sends rich email in TNEF format.

This appear to be the Microsoft support documentation for that.