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firefox fresh install not working on fresh windows 10 install

  • 3 replies
  • 1 has this problem
  • 5 views
  • Last reply by FredMcD

conner1245
conner1245
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I did a fresh install of windows and a fresh install of firefox and in getting SEC_ERROR_UNKNOWN_ISSUER every time I try to go to google. I tried the about:config fix and that didn't work for me. it says that the site is using hsts specify that Firefox may only connect to it securely. I'm using my private home network for internet.

I did a fresh install of windows and a fresh install of firefox and in getting SEC_ERROR_UNKNOWN_ISSUER every time I try to go to google. I tried the about:config fix and that didn't work for me. it says that the site is using hsts specify that Firefox may only connect to it securely. I'm using my private home network for internet.

Chosen solution

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


  • MOZILLA_PKIX_ERROR_MITM_DETECTED
  • 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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All Replies (3)

FredMcD
FredMcD
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Chosen Solution

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


  • MOZILLA_PKIX_ERROR_MITM_DETECTED
  • 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

conner1245
conner1245 Question owner
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i dont have an anti virus program other then windows defender

FredMcD
FredMcD
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Has the problem been solved?