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S/MIME can´t find the certificate

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The S/MIME e-signature does not function. (The problem occurred recently.) The system can not find the certificate (the certificate is valid, it is QCA23....73.crt). How the system searches for it? What should I set in Thunderbird to find it? The openPGP functions well.

The S/MIME e-signature does not function. (The problem occurred recently.) The system can not ''find'' the certificate (the certificate is valid, it is QCA23....73.crt). How the system searches for it? What should I set in Thunderbird to find it? The openPGP functions well.

All Replies (3)

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Hello there We have read the message We try to help

About SHA_1 use. And signatures.

Good day. From the release Thunderbird 115.0 it no longer accepts SHA-1 signatures.

Some government agencies continue to use this reference to send email to third parties. Thunderbird has made a concession here in an option to use this as

mail.smime.accept_SHA1_message_signatures .

Which makes this possible. Enabling this is not recommended by the development team.

Senders to you should be informed to switch to SHA-256 for signature migration.

After using the exemption option, the recommendation would be to disable it immediately after use.

This adjustment cannot be influenced for properly sent mail traffic that uses SHA_256.

Nowadays, after the launch of version Thunderbird 115.0, if this SHA_1 method is used, you will receive a message as you received on your PC screen.


Greetings Firefox volunteer

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Hello there


The function to use this option will be set in version 115.4.1

To enable it, use Thunderbird's settings, open the advanced configuration editor, look for the settingmail.smime.accept_insecure_sha1_message_signatures and set it to the value true.



Greetings Firefox volunteer

Modified by Googlethunderbird

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Hello there

https://www.thunderbird.net/en-US/thunderbird/releases/


Greetings Firefox volunteer