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I installed Firefox for the Mac and when I try to go to any website it says that the site is insecure and won't let me continue. How can I correct this error?

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  • Last reply by FredMcD

khalil11111
khalil11111
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I installed firefox quantum but it won't let me access any websites. I tried google, yahoo, etc. and it always gives me the message:

The owner of www.facebook.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.

I get this error message for all sites...

I installed firefox quantum but it won't let me access any websites. I tried google, yahoo, etc. and it always gives me the message: The owner of www.facebook.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. I get this error message for all sites...

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