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Not a Valid Signature Error While Other Clients Validate It

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Michael Fuchs
Michael Fuchs
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Hi everyone,

I'm encountering an issue with Thunderbird (version 128.5.1.esr) on Windows 11 with the latests updates that I can't seem to figure out. Whenever I receive a digitally signed email, Thunderbird reports that the signature is "not valid" accoridng to the provided screenshot.

Here's the strange part:

The same email shows a valid signature in other mail clients, including Outlook (iOS, Android, Windows, macOS) and Apple Mail on macOS.

The email is sent using a golan application (GitHub Repo https://github.com/theexiile1305/go-mail) , so it should be consistent across the board.

I can't understand why Thunderbird alone is flagging this as invalid. Has anyone else faced this issue or knows what might be causing it? Could it be related to how Thunderbird verifies signatures or interacts with certain certificates? How can I access the logs to get a deeper insight into this issue?

Thanks in advance for any insights!

Hi everyone, I'm encountering an issue with Thunderbird (version 128.5.1.esr) on Windows 11 with the latests updates that I can't seem to figure out. Whenever I receive a digitally signed email, Thunderbird reports that the signature is "not valid" accoridng to the provided screenshot. Here's the strange part: The same email shows a valid signature in other mail clients, including Outlook (iOS, Android, Windows, macOS) and Apple Mail on macOS. The email is sent using a golan application (GitHub Repo https://github.com/theexiile1305/go-mail) , so it should be consistent across the board. I can't understand why Thunderbird alone is flagging this as invalid. Has anyone else faced this issue or knows what might be causing it? Could it be related to how Thunderbird verifies signatures or interacts with certain certificates? How can I access the logs to get a deeper insight into this issue? Thanks in advance for any insights!
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