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Small and medium business | Business Central, N...
Answered

'Failure sending mail. Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host.'

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Posted on by 85

Hi everyone I have implemented some mail sending functionality to send(Posted Sales Invoices) with custom email body, when I try to send multiple it send few of them and show message that enable to send email, If I try to debug it show them following error.

Please suggest a solution design change or code imporvement thanks

7217.SMTP-error.png

CLEARALL();
SMTPSetup.GET;
IF customer.GET(SalesHeaders."Sell-to Customer No." )THEN
 customer.TESTFIELD("E-Mail");
 CompanyInfo.GET();
 WITH TempEmailItem DO BEGIN
      "From Address" := SMTPSetup."User ID";
      "Send to" := customer."E-Mail";
      Subject := CompanyInfo.Name ' - Invoice '   SalesHeaders."No.";
      GenerateEmailBody(SalesHeaders, EmailBody);
      Body := EmailBody.Blob;
      "Attachment File Path":= GenerateEmailAttachment(SalesHeader."No.");;
      "Attachment Name" := 'Sales Invoice ' SalesHeader."No." '.pdf';
      "Plaintext Formatted" := FALSE;
      EXIT(Send(TRUE));
 END;

I have the same question (0)
  • Verified answer
    Marco Mels Profile Picture
    Microsoft Employee on at

    Hello,

    Usually this error related to Tls1.2 requirements that are not met. The forum has a few suggestions that you can follow up on, using registry. Tls1.2 was only added in Dynamics NAV xxx in a specific cumulative update.

    Thanks.

  • Verified answer
    Abdullah Zafar Profile Picture
    85 on at

    Thank you Marco Mels , The issue was due to the TLS version, to resolve I had added dotnet variable in function TrySend of codeunit 400. I have followed this guide from Erik Hougaard  

    Link www.hougaard.com/.../

    Best Regards

  • bruno.a.paulo@outlook.pt Profile Picture
    5 on at

    Hi Abdullah Zafar,

    Can you send a print of the function "TrySend" of codeunit "400" please

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