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Small and medium business | Business Central, N...
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Mails from BC fails - cannot be created .NET Framework-objekt: montage MimeKit

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When trying to send invoices from Business Central today we get the following error message:

An instance of the following cannot be created .NET Framework-objekt: montage MimeKit, Version=2.2.0.0, Culture=neutral, PublicKeyToken=bede1c8a46c66814, type MimeKit.MimeMessage.

It is Business Central in the Microsoft cloud application version 19.2.32968.33612

Do you have any idea why we get this error today and not yesterday?

Azure AD tenant: c083c0e2-df95-47a5-aefb-8d571d6d5ba0, Environment: Production (Production)
Session ID (client): dfbb34a2-d8eb-4982-95df-052e1a31700a
Session ID (server): 1196
Email-Accounts.jpgFailed-mails.jpg

Best wishes

Martin Johnsen

I have the same question (0)
  • Suggested answer
    IB-29041624-0 Profile Picture
    1,191 Moderator on at

    If you have the same issue as in this case: community.dynamics.com/.../cannot-create-an-instance-of-the-following-net-framework-object-assembly-mimekit-version-2-2-0-0-culture-neutral-publickeytoken-bede1c8a46c66814-type-mimekit-mimemessage-error-in-dynamics-365-business-central-saas-for-dk-is-n

    Then it should be solved now. If not you should raise a supportcase through your CSP partner.

  • Community Member Profile Picture
    on at

    Thank you for finding this link for me. We still have the problem, but will see if it will work tomorrow, as it seems that they are still working on it. This is the error from sending a test mail.

    mail-fail-100122.jpg_2D00_640x480.jpg

  • Suggested answer
    Marco Mels Profile Picture
    Microsoft Employee on at

    Hello,

    The issue should have been resolved by now. If not, please raise it so we can look at this individual tenant.

    Thanks.

  • Suggested answer
    Community Member Profile Picture
    on at

    Hi Marco

    We still had problems this morning by this customer.

    I have today tried to send a test mail from the Mail Account, where it still fails, but the error is now: Cannot authenticate the credentials on server smtp.office365.com

    I then tried to go to the SMTP Mail Setup and reenter the password, then I could make a succesful test from that page. Going back to Mail Account to make a test, it still fails. I have now reentered the password under Email Accounts, and click the mail address. 

    It seems like you have to enter the password in 2 simular pages before it takes effect. (SMTP Account and SMTP Mail Setup)

    For now it seems to work. Thanks for you reply :-)

    Mail-SMTP.jpgMail-SMTP-success.jpgMails-Failed-2022_2D00_01_2D00_12.jpgMail-Account.jpgMails-received.jpg_2D00_640x480.jpg_2D00_640x480.jpg

  • Suggested answer
    Marco Mels Profile Picture
    Microsoft Employee on at

    Hello,

    Great to hear this. Best is to not use legacy SMTP Server and only use Email accounts where you use OAUTH instead of Basic. Basic Authentication will be deprecated at some point in time by Exchange Server team (which is a good thing they should do).

    Thanks.

  • Community Member Profile Picture
    on at

    Thanks for this answer. The e-mail is set up in Office 365, and in BC we have just pressed "Apply Office 365 Server Settings". Do you know if we just can change the "Authentication" from Basic to OAuth2.0 or is it a general setting in Office 365 that needs to be changed?

  • Suggested answer
    Marco Mels Profile Picture
    Microsoft Employee on at

    Hello,

    If hosted by Microsoft in SaaS, it will work out of the box after flipping authentication type from Basic to OAUTH2.0.

    Thanks.

  • Community Member Profile Picture
    on at

    Hi Marco

    I have switched the setting from Basic to Oauth2.0 in BC. It seems to work sending mails, but sendt mails are not stored in the Sent mails folder in the mailbox. Do you know if that is a result of this change and if there is a setting we can change to activate that feature?

    The mail-box they send from is a standard mailbox that the users have access to and allowed to send from (not shared mailbox). They have the standard type because they want all send mails to be stored in the sent mail, and that is not possible with a shared mailbox.

    Best wishes

    Martin Johnsen

  • Suggested answer
    Marco Mels Profile Picture
    Microsoft Employee on at

    Hello,

    I quickly ran the scenario on my SaaS BC tenant and in Outlook I see my Sent Items folder with the mails I sent.

    For the test I opened a user card that has the mail address filled in and sent a mail to the customer (demo user) and I send a test mail (via current user connector). Are your users testing in a different way or using a different connection, like SMTP connector?

    Thanks.

  • Community Member Profile Picture
    on at

    Thank you for following up :-) The scenario is that the mail account "faktura" (invoice in Danish) is set up as the default mail account in BC, so users send invoices and other documents from BC to the customers. If I log in as faktura (which has a BC license attached) and send an e-mail, it will be stored in Sent mails on Outlook. If I log in as another user the mails are not stored in the sent mail in the faktura mailbox. Before I changed the setting from Basic to Oauth2.0 it stored all mails in the mailbox of faktura as expected.

    The user I normal use does not have an e-mail, so after the change I can not send e-mails from BC with that user, but I guess that is the point with the setting, to check that I am allowed to send from the faktura-mailbox - so that is fine :-) It is just an issue we have to face when changing this setting.

    Best wishes

    Martin Johnsen

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