Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Thunderbird cannot detect CA Certificate

  • 7 replies
  • 1 has this problem
  • 19 views
  • Last reply by christ1

more options

Hello, I created a certificate backup that came from the browser and saved it on the desktop. But when I try to import it at Mozilla Thunderbird it says "Certificate Manager can't locate a valid certificate that can be used to digitally sign your messages with an address of <[email protected]>"

I also tried manually importing it using "Manage Certificates" but it doesn't detect the CA cert also

I'm using Ubuntu, how do I solve this problem?

Hello, I created a certificate backup that came from the browser and saved it on the desktop. But when I try to import it at Mozilla Thunderbird it says "Certificate Manager can't locate a valid certificate that can be used to digitally sign your messages with an address of <[email protected]>" I also tried manually importing it using "Manage Certificates" but it doesn't detect the CA cert also I'm using Ubuntu, how do I solve this problem?

All Replies (7)

more options
I also tried manually importing it using "Manage Certificates" but it doesn't detect the CA cert also

I'm not sure what the 'detect the CA cert' part is all about. Can you elaborate?

more options

christ1 said

I also tried manually importing it using "Manage Certificates" but it doesn't detect the CA cert also

I'm not sure what the 'detect the CA cert' part is all about. Can you elaborate?

When I manually import the cert using the "Manage Certificates" on thunderbird it doesn't appear on the certificates list

more options

What kind of cert, i.e. for what purpose, are you trying to import?

Underneath which tab are you trying to import the cert (Your Certificates, People, Servers, or Authorities)?

If a personal cert for email signing, did you also export the private key along with the cert?

more options

christ1 said

What kind of cert, i.e. for what purpose, are you trying to import? Underneath which tab are you trying to import the cert (Your Certificates, People, Servers, or Authorities)? If a personal cert for email signing, did you also export the private key along with the cert?

I'm using COMODO Free Email Cert

I figured it out now, I tried sending first a Signed Email, how will I know if it's signed or not?

more options
how will I know if it's signed or not?

When a message is signed there's an envelope button on the right in the header area of the message window . Press the button.

more options

Thanks!

The recipient of the email replied to me with a different certificate I tried replying to him with an encrypted message and it says: "Unable to save your message as a draft. You specified encryption for this message, but the application failed to find an encryption certificate"

Is it because I don't trust the certificate yet?

more options

OP started a duplicate topic at https://support.mozilla.org/en-US/questions/1250241

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?

Then check your Thunderbird certificate store whether you do have the COMODO RSA Client Authentication and Secure Email CA cert underneath 'Authorities'.

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 [email protected]

Assuming the certificate for [email protected] is your own one, make sure you properly linked it to your account in Thunderbird Account Settings - Security.