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Thunderbird doesn't trust a valid CA Certificate

  • 2 replies
  • 1 has this problem
  • 8 views
  • Last reply by christ1

ecksdee
ecksdee
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So basically I sent a digitally signed email using a certificate issued by Sectigo RSA Client Authentication and Secure Email CA.

Now the recipient of the email replied to me with a certificate issued by COMODO RSA Client Authentication and Secure Email CA, but it says the Digital Signature is invalid? Why is it invalid?

I got an error when I try to reply back with a digitally signed and encrypted email:

Sending of the message failed. You specified encryption for this message, but the application failed to find an encryption certificate for johndoe@gmail.com

What I have tried so far:

Exported the .crt then import it on "Manage Certificates" People's Tab

But still got an error when trying to reply to the email

So basically I sent a digitally signed email using a certificate issued by Sectigo RSA Client Authentication and Secure Email CA. Now the recipient of the email replied to me with a certificate issued by COMODO RSA Client Authentication and Secure Email CA, but it says the Digital Signature is invalid? Why is it invalid? I got an error when I try to reply back with a digitally signed and encrypted email: Sending of the message failed. You specified encryption for this message, but the application failed to find an encryption certificate for johndoe@gmail.com What I have tried so far: Exported the .crt then import it on "Manage Certificates" People's Tab But still got an error when trying to reply to the email

All Replies (2)

ecksdee
ecksdee Question owner
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Here's a screenshot, it doesn't trust COMODO CA

christ1
christ1
  • Top 25 Contributor
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Please stick to your original topic at https://support.mozilla.org/en-US/questions/1250241