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Firefox doesn't load any website from now on and tells me "this connection is not secure". What can I do? I need to have access to my tabs in firefox again. Thx

  • 3 பதிலளிப்புகள்
  • 1 இந்த பிரச்சனை உள்ளது
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  • Last reply by FredMcD

Dear ladies and gentlemen, unfortunately my firefoy today told me that a security program (this note was coming from my kaspersky security system, but it said that there is another system which wants to secure my browser) wants to secure my browser and I said "accept". Afterwards I coulnd`t load any websites anymore cause Firefox always tells me "this connection is not secure". I can not add exceptions. Afterwards I deactivated the security System in the add-ons again but I still have the problem that I can't load any page with firefox. I can't find any security setting to help me. Firefox tells me:"Fehlercode: SEC_ERROR_UNKNOWN_ISSUER" I also can't leave this website and send the error to Mozilla (as you can see on the added picture). Can you please help me and tell me what I can do to be able to use Firefox and all my safed tabs again? Thank you very much! Yours sincerely, Melanie Westermann

Dear ladies and gentlemen, unfortunately my firefoy today told me that a security program (this note was coming from my kaspersky security system, but it said that there is another system which wants to secure my browser) wants to secure my browser and I said "accept". Afterwards I coulnd`t load any websites anymore cause Firefox always tells me "this connection is not secure". I can not add exceptions. Afterwards I deactivated the security System in the add-ons again but I still have the problem that I can't load any page with firefox. I can't find any security setting to help me. Firefox tells me:"Fehlercode: SEC_ERROR_UNKNOWN_ISSUER" I also can't leave this website and send the error to Mozilla (as you can see on the added picture). Can you please help me and tell me what I can do to be able to use Firefox and all my safed tabs again? Thank you very much! Yours sincerely, Melanie Westermann

தீர்வு தேர்ந்தெடுக்கப்பட்டது

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

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தீர்வு தேர்ந்தெடுக்கப்பட்டது

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

Glad to help. Safe Surfing.