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Any idea how I fix this? It comes up often.

  • 6 cavab
  • 3 have this problem
  • 7 views
  • Last reply by James

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I just downloaded Quantum but can't do much as I keep getting this message.

accounts.firefox.com uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported. Error code: SEC_ERROR_UNKNOWN_ISSUER

When I click advanced, I get the following:

https://accounts.firefox.com/signup?service=sync&context=fx_desktop_v3&entrypoint=uitour&utm_campaign=page+referral+-+not+part+of+a+campaign&utm_content=%2Ffirefox%2Ffeatures%2Fsync%2F

Peer’s Certificate issuer is not recognized.

HTTP Strict Transport Security: true HTTP Public Key Pinning: true

Certificate chain:

Any assistance would be appreciated

I just downloaded Quantum but can't do much as I keep getting this message. accounts.firefox.com uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported. Error code: SEC_ERROR_UNKNOWN_ISSUER When I click advanced, I get the following: https://accounts.firefox.com/signup?service=sync&context=fx_desktop_v3&entrypoint=uitour&utm_campaign=page+referral+-+not+part+of+a+campaign&utm_content=%2Ffirefox%2Ffeatures%2Fsync%2F Peer’s Certificate issuer is not recognized. HTTP Strict Transport Security: true HTTP Public Key Pinning: true Certificate chain: Any assistance would be appreciated

Chosen solution

You can click the "Advanced" button to expand this section and show extra details. If the certificate is not trusted (SEC_ERROR_UNKNOWN_ISSUER) then click the blue error message to expand this section and show the certificate chain. You can click "Copy text to clipboard" and paste this base64 encoded certificate chain text in a reply. That will allow us to details like the issuer of the certificate.

  • always be cautious when you get an 'Untrusted' error message
  • never create a permanent exception without investigating the cause and only use this to inspect the certificate
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All Replies (6)

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My knowledge of these sorts of things is very limited so please excuse me if I'm misunderstanding this.

The link above states that the owner of the website that I was trying to access has configured it improperly. I use Kaspersky, so it appears to offer workarounds within Kaspersky to still access the site.

The website I'm trying to access though is https://accounts.firefox.com/ Shouldn't the Firefox site be configured properly?

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I think Kaspersky is part of the cause here. I run FF58x64 with Defender and Windows Firewall and have no issue logging into my FF account.

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Seçilmiş Həll

You can click the "Advanced" button to expand this section and show extra details. If the certificate is not trusted (SEC_ERROR_UNKNOWN_ISSUER) then click the blue error message to expand this section and show the certificate chain. You can click "Copy text to clipboard" and paste this base64 encoded certificate chain text in a reply. That will allow us to details like the issuer of the certificate.

  • always be cautious when you get an 'Untrusted' error message
  • never create a permanent exception without investigating the cause and only use this to inspect the certificate
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No idea what happened, but when I tried to access the site this morning, it went through without any difficulty. Thanks for your replies!

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debnkev said

The website I'm trying to access though is https://accounts.firefox.com/ Shouldn't the Firefox site be configured properly?

The Mozilla site is configured properly, just that antivirus clients such as Kaspersky can insert their own certificate in their attempt at keeping you safe only to instead cause this SEC_ERROR_UNKNOWN_ISSUER error. This feature antivirus clients should be disabled by default overall.