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My Firefox 15.0.1 cannot verify any SSL CA, it says:"Cound not verify this certificate for unknown reasons." when I view the certificate status.

  • 4 replies
  • 2 have this problem
  • 8 views
  • Last reply by apoph1s

apoph1s
apoph1s
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I recently switched to Windows 8 (from 7) and installed Firefox 15.0.1. Whenever I try to access a http secure page I get a message that "This Connection is Untrusted". If I click the Add exception button and view the certificate status I get the following message every time: "Cound not verify this certificate for unknown reasons."

I checked these sites in other browsers and they work just fine. I also checked the certificates using this site: http://www.networking4all.com/en/support/tools/site+check/

I've alreary tried to run firefox in compatibility mode and when that didn't help I reinstalled it but nothing's changed. I'm using chrome for the time being but I hope it's not the only solution.

I recently switched to Windows 8 (from 7) and installed Firefox 15.0.1. Whenever I try to access a http secure page I get a message that "This Connection is Untrusted". If I click the Add exception button and view the certificate status I get the following message every time: "Cound not verify this certificate for unknown reasons." I checked these sites in other browsers and they work just fine. I also checked the certificates using this site: http://www.networking4all.com/en/support/tools/site+check/ I've alreary tried to run firefox in compatibility mode and when that didn't help I reinstalled it but nothing's changed. I'm using chrome for the time being but I hope it's not the only solution.

Chosen solution

Which security software (firewall, anti-virus) do you have?

Some firewalls monitor secure (https) connections and send their own certificate instead of the website's certificate.

You can retrieve the certificate and check details like who issued certificates and expiration dates of certificates.

  • Click the link at the bottom of the error page: "I Understand the Risks"

Let Firefox retrieve the certificate: "Add Exception" -> "Get Certificate".

  • Click the "View..." button and inspect the certificate and check who is the issuer.

You can see more Details like intermediate certificates that are used in the Details pane.

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All Replies (4)

ErikaV
ErikaV
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Make sure SSL protocols are selected in firefox.

Go to Tools-->Options-->Advanced-->Encryption

Under protocols make sure both SSL and TLS are checked.

Modified by ErikaV

apoph1s
apoph1s Question owner
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Thanks for the answer, but both SSL 3 and TLS 1 are checked.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Chosen Solution

Which security software (firewall, anti-virus) do you have?

Some firewalls monitor secure (https) connections and send their own certificate instead of the website's certificate.

You can retrieve the certificate and check details like who issued certificates and expiration dates of certificates.

  • Click the link at the bottom of the error page: "I Understand the Risks"

Let Firefox retrieve the certificate: "Add Exception" -> "Get Certificate".

  • Click the "View..." button and inspect the certificate and check who is the issuer.

You can see more Details like intermediate certificates that are used in the Details pane.

apoph1s
apoph1s Question owner
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Thanks cor-el, you were totally right. I don't know how I didn't noticed that the certificate issuer was ESET in all cases. I refined my google search with this and found the same issue and the solution which was also provided by you. (https://support.mozilla.org/en-US/questions/923516)

So I turned off the SSL protocol filtering in ESET and the problem disappeared.