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Cant access websites : HTTP Strict Transport Security (HSTS)

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

guardian007
guardian007
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From today morning I am not able to access most of the websites through firefox. The browser is up to date and I tried clearing cookies and caches as well. I am not even able to access mozilla website.

It always displays the following warning : "The owner of www.google.com has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website.

This site uses HTTP Strict Transport Security (HSTS) to specify that Firefox may only connect to it securely. As a result, it is not possible to add an exception for this certificate."

From today morning I am not able to access most of the websites through firefox. The browser is up to date and I tried clearing cookies and caches as well. I am not even able to access mozilla website. It always displays the following warning : "The owner of www.google.com has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website. This site uses HTTP Strict Transport Security (HSTS) to specify that Firefox may only connect to it securely. As a result, it is not possible to add an exception for this certificate."

All Replies (1)

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

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

Websites don't load - troubleshoot and fix error messages

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