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sec_error_unknown_issuer

  • 5 replies
  • 22 have this problem
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  • Last reply by user_0

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For every sites I get "Secure Connection Failed", e.g., static-cdn.addon.mozilla.net:443 uses an invalid security certificate. I am running Firefox 5. I tried couple of times uninstalling Firefox and deleting profile; I used Winutilities to clean registry. Nothing seems to work, the webpages do not load properly. I tried to run firefox without any addon installed, same result. I think it's some configuration or registry problem, because opera, IE works without problem.

For every sites I get "Secure Connection Failed", e.g., static-cdn.addon.mozilla.net:443 uses an invalid security certificate. I am running Firefox 5. I tried couple of times uninstalling Firefox and deleting profile; I used Winutilities to clean registry. Nothing seems to work, the webpages do not load properly. I tried to run firefox without any addon installed, same result. I think it's some configuration or registry problem, because opera, IE works without problem.

All Replies (5)

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You have a corrupted user agent that identifies you as

  • Mozilla/5.0 (Windows NT 6.1; WOW64; rv:5.0.1) Gecko/20100101 Firefox/5.0.1HTTcryPt/Add-on

See:

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I have reset the useragent, now

general.useragent.compatMode.firefox;false general.useragent.locale;en-US

However, I am still having the same problem.

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Did you check your security software (firewall)?

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

You can retrieve the certificate and check who issued the certificate.

  • 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 to inspect the certificate and check who is the issuer.

Try to remove all rules for Firefox from the permissions list in the firewall and let your firewall ask again for permission to get full unrestricted access to internet for Firefox and the plugin-container process and the updater process.

See:

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I am useing BitDefender and as you suspected they send their own certificate. I checked "Certificate Manager" by selection Tools -> Options -> Advanced -> Encryption -> View Certificates -> Servers. I have contacted BitDefender and waiting for their reply.

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I uninstalled old BitDefender and installed BitDefender 2012, still geting the same error.