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S/MIME and trusting other certificates

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  • Last reply by alan158

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I am trying to get S/MIME set up properly. I have my personal certificate set up and installed - I can send signed messages. However, when I try to send an ecrypted message to a recipent with a DOD certificate, I run into an error that the certificate is not valid. I have installed the DOD root certificates, trusted them for email/websites, and imported the individual's signature cert into the store.

How do I change the settings / trust on the individual's certificate to trust it? It is within the valid date range.

I am trying to get S/MIME set up properly. I have my personal certificate set up and installed - I can send signed messages. However, when I try to send an ecrypted message to a recipent with a DOD certificate, I run into an error that the certificate is not valid. I have installed the DOD root certificates, trusted them for email/websites, and imported the individual's signature cert into the store. How do I change the settings / trust on the individual's certificate to trust it? It is within the valid date range.

Chosen solution

I had already installed the DOD root certificates as you had mentioned.

I had to manually go through each DOD certificate and "Edit Trust" to allow them to identify websites and email. That solved the problem.

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Generally the issue is missing intermediate certificates. But Personally I think it is funny the supposedly most secure organizations in the world can't meet a public test on their integrity that would see them included in the trusted authorities immediately.

However basically I suggest following the guide for Firefox here https://public.cyber.mil/pki-pke/end-users/getting-started/linux-firefox/

So Step 1 from the web site In Thunderbird open options/ preferences and search for cert then click the Manage Certificates button. The pages are generally the same in Thunderbird and Firefox as Thunderbird uses the same pki code to manage certificates as Firefox. Skip to step 7. from the web site

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Chosen Solution

I had already installed the DOD root certificates as you had mentioned.

I had to manually go through each DOD certificate and "Edit Trust" to allow them to identify websites and email. That solved the problem.

Modified by alan158