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Certificate errors prevent me from accessing safe sites

  • 3 replies
  • 1 has this problem
  • 1 view
  • Last reply by FredMcD

MadScientist8
MadScientist8
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I am unable to access my gmail account or my Linkedin account with FireFox. I get a certificate error SEC_ERROR_UNKNOWN_ISSUER yet this is a valid site and account. When Firefox gives the error it will not allow me to add a certificate exception, so I cannot use Firefox for these sites and probably others.

I am unable to access my gmail account or my Linkedin account with FireFox. I get a certificate error SEC_ERROR_UNKNOWN_ISSUER yet this is a valid site and account. When Firefox gives the error it will not allow me to add a certificate exception, so I cannot use Firefox for these sites and probably others.

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

Read this answer in context 👍 1

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

MadScientist8
MadScientist8 Question owner
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All I can say is Thank you

FredMcD
FredMcD
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Glad to help. Safe Surfing.