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Problem with s/MIME encryption Protocol.

  • 10 replies
  • 1 has this problem
  • 1 view
  • Last reply by christ1

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Good afternoon. There is a PFX certificate that is registered in MS Outlook and thunderbird. When you try to send an encrypted s/MIME Protocol to an email from MS Outlook, the email arrives encrypted. But when I try to send an encrypted email using s / MIME with thunderbird to MS Outlook, the email is sent unencrypted. What could be the problem?

Good afternoon. There is a PFX certificate that is registered in MS Outlook and thunderbird. When you try to send an encrypted s/MIME Protocol to an email from MS Outlook, the email arrives encrypted. But when I try to send an encrypted email using s / MIME with thunderbird to MS Outlook, the email is sent unencrypted. What could be the problem?

All Replies (10)

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Have you specified the PFX-certificate in the account settings in the Security pane for Digital Signing and Encryption?

In the Message Compose window, did you choose Options > Encrypt This Message?

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Yes, the PFX certificate is selected there. Before sending the letters, indicate the Protocol encryption and put a tick encrypt this letter.

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Protocol encryption is not in the standard options. Do you have Enigmail installed? Maybe Enigmail takes precedence before Thunderbird's native S/MIME encryption.

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Yes. The enigmail plugin is installed.

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Sorry, I don't have Enigmail installed on this computer, so I can't find the exact options in Enigmail or check if this works, but you should choose Options > Encrypt This Message from the menu instead of Enigmail > Protocol encryption…

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The enigmail plugin is installed.

Which version? And it's an extension, not a plugin. Terminology matters.

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Oh, sorry. Gnupg plugin version 2.1.18 is installed. The enigmail extension is version 2.0.3. Thunderbird version 52.3.0.

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Enigmail version 2.0.3 is the latest one and should work. The gnupg version is irrelevant for S/MIME. Can you try to disable Enigmail, and restart Thunderbird? Does S/MIME encryption work then?

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Tried, not working.

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Create a new profile, set up your account, and try again. https://support.mozilla.org/en-US/kb/using-multiple-profiles

No extensions are needed for S/MIME.

Modified by christ1