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Connection Not Secure Error On All Websites??

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

thecolbster91
thecolbster91
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Hello, Last week my Firefox browser was working fine, but now for the last couple of days almost every site I go to says "Your connection is not secure The owner of "such and such" has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website." And also I get an error that says: "The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported. Error code: SEC_ERROR_UNKNOWN_ISSUER" I've tried deleting my anti-virus program, McAfee, I've reinstalled Firefox. It did not work. Could it be a computer issue or a wifi issue?? I'm using version 63.0.3

Hello, Last week my Firefox browser was working fine, but now for the last couple of days almost every site I go to says "Your connection is not secure The owner of "such and such" has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website." And also I get an error that says: "The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported. Error code: SEC_ERROR_UNKNOWN_ISSUER" I've tried deleting my anti-virus program, McAfee, I've reinstalled Firefox. It did not work. Could it be a computer issue or a wifi issue?? I'm using version 63.0.3

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


  • 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