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I received a signed email (signed by IdenTrust) that Thunderbird says the signature is invalid. It says that I don't trust the cert. authority. Help please.

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  • Last reply by christ1

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I sent a signed email from my work to home (which uses Thunderbird). I can read the email ok but get the following certificate error:

This message includes a digital signature, but the signature is invalid. The certificate used to sign the message was issued by a certificate authority that you do not trust for issuing this kind of certificate.

The issuing authority is: IdenTrust ECA 3

How can I mitigate this issue? I will need to send encrypted emails back and forth but without this working, it's impossible.

Thanks in advance.

I sent a signed email from my work to home (which uses Thunderbird). I can read the email ok but get the following certificate error: This message includes a digital signature, but the signature is invalid. The certificate used to sign the message was issued by a certificate authority that you do not trust for issuing this kind of certificate. The issuing authority is: IdenTrust ECA 3 How can I mitigate this issue? I will need to send encrypted emails back and forth but without this working, it's impossible. Thanks in advance.

Chosen solution

You'll have to have to root CA cert in the Thunderbird certificate store under the Authorities tab. The error message suggests that the cert exists, but you'll have to edit the trust.

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You can edit the trust for the cert via Tools (Alt-T) - Options - Advanced - View Certificates - Authorities tab

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Thank you very much for your reply. It is greatly appreciated.

I took a look there and IdenTrust isn't listed. How can I get what I need (I am assuming a cert) from IdenTrust making them a trusted authority?

Thanks again in advance.

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Chosen Solution

You'll have to have to root CA cert in the Thunderbird certificate store under the Authorities tab. The error message suggests that the cert exists, but you'll have to edit the trust.

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That was where the issue was. I had to export the root CA from another PC and import it to the one in question. Everything works great now.

Thank you for your help.

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Thanks for the feedback. When your problem has been fixed can you mark this thread as 'Solved' please? Thank you.