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Updated Firefox Now Insecure Connection for every website

  • 1 reply
  • 7 have this problem
  • 5 views
  • Last reply by FredMcD

icomputeuk
icomputeuk
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Just updated to Firefox 58.0.1 for Mac running El Capitan 10.11.6 and every single HTTPs website is blocked with SEC_ERROR_UNKNOWN_ISSUER insecure connection.

Have refreshed Firefox. Disabled all extensions and addons and (being a Mac) have no security software that could potentially mess with it.

It was literally working just minutes ago with the previous version of Firefox and there assume it must be an issue with the update.

Please help. I'm having to use Safari which I hate!

Just updated to Firefox 58.0.1 for Mac running El Capitan 10.11.6 and every single HTTPs website is blocked with SEC_ERROR_UNKNOWN_ISSUER insecure connection. Have refreshed Firefox. Disabled all extensions and addons and (being a Mac) have no security software that could potentially mess with it. It was literally working just minutes ago with the previous version of Firefox and there assume it must be an issue with the update. Please help. I'm having to use Safari which I hate!

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