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SEC_ERROR_UNKNOWN_ISSUER

cchoy
cchoy
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I suddenly started getting this error on sites like Google and Facebook. I have Avast and disabling the HTTPS scanning works but I want to find a solution that doesn't involve that. I've tried looking for the Microsoft Family Saftey Certificate and importing it but my machine doesn't appear to have it. Is there some other certificate package I can import to fix this issue?

I suddenly started getting this error on sites like Google and Facebook. I have Avast and disabling the HTTPS scanning works but I want to find a solution that doesn't involve that. I've tried looking for the Microsoft Family Saftey Certificate and importing it but my machine doesn't appear to have it. Is there some other certificate package I can import to fix this issue?

All Replies (2)

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

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 10 Contributor
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Avast often can set up Firefox automatically for you but, if that doesn't work, you probably can import the "signing certificate" it uses to generate those fake site certificates Firefox doesn't like. Searching here can be frustrating because older threads often come up first, and it's important to get the instructions for your current version of Avast. You might have better luck on the Avast forums.