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"Insecure Connection" with many webistes, incl. mozilla.com -- Firefox does not open sites due certificate issues

  • 1 reply
  • 1 has this problem
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  • Last reply by FredMcD

peter.petermann
peter.petermann
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I am tryin to access several websites from my Firefox browser, including mozilla's own support site; but all I get is an error page telling my that the certificate is not accepted because "the owner of the website did not confgure their website correctly". I did not use to have this problem, it started occuring about 1 week ago -- and surely, there is something iherently wrong if even your own site is not acceptable. I have uninstalled and re-installed Firefox already but the problem persists. Please let me know what I need to configure to solve this issue. Thanks (PS: I accessing your support page through my IE 11 browser)

I am tryin to access several websites from my Firefox browser, including mozilla's own support site; but all I get is an error page telling my that the certificate is not accepted because "the owner of the website did not confgure their website correctly". I did not use to have this problem, it started occuring about 1 week ago -- and surely, there is something iherently wrong if even your own site is not acceptable. I have uninstalled and re-installed Firefox already but the problem persists. Please let me know what I need to configure to solve this issue. Thanks (PS: I accessing your support page through my IE 11 browser)

All Replies (1)

FredMcD
FredMcD
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There is security software like Avast, Kaspersky, BitDefender and ESET that intercept secure connections and send their own certificate.

https://support.mozilla.org/en-US/kb/firefox-cant-load-websites-other-browsers-can

https://support.mozilla.org/en-US/kb/firefox-and-other-browsers-cant-load-websites

https://support.mozilla.org/en-US/kb/secure-connection-failed-error-message

https://support.mozilla.org/en-US/kb/connection-untrusted-error-message

http://kb.mozillazine.org/Error_loading_websites


  • uses an invalid security certificate SSL_ERROR_BAD_CERT_DOMAIN
  • configured their website improperly

How to troubleshoot the error code "SEC_ERROR_UNKNOWN_ISSUER" on secure websites https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER