Recent answers to SEC_ERROR_UNKNOWN_ISSUER to every site that use HSTS.https://support.mozilla.org/km/questions/13101972020-10-26T02:53:05-07:00Who is the issuer of the certificate ?
You can check details about the issuer of the certificat2020-10-26T02:53:05-07:00cor-elhttps://support.mozilla.org/km/questions/1310197#answer-1361375<p>Who is the issuer of the certificate&nbsp;?
</p><p>You can check details about the issuer of the certificate and the certificate chain.
</p>
<ul><li>click the "Advanced" button on the error page to show more detail
</li><li>click the blue "View Certificate" text to inspect the certificate chain in the Certificate Viewer
</li></ul>There is security software like Avast, Kaspersky,
BitDefender and ESET that intercept secure
connect2020-10-25T15:23:20-07:00fredmcd-hotmailhttps://support.mozilla.org/km/questions/1310197#answer-1361283<p>There is security software like Avast, Kaspersky,
BitDefender and ESET that intercept secure
connection certificates and send their own&#46;
</p><p>https://support&#46;mozilla&#46;org/en-US/kb/firefox-cant-load-websites-other-browsers-can
</p><p>https://support&#46;mozilla&#46;org/en-US/kb/firefox-and-other-browsers-cant-load-websites
</p><p>https://support&#46;mozilla&#46;org/en-US/kb/secure-connection-failed-error-message
</p><p>https://support&#46;mozilla&#46;org/en-US/kb/connection-untrusted-error-message
</p><p><a href="https://support&#46;mozilla&#46;org/en-US/kb/websites-dont-load-troubleshoot-and-fix-errors?redirectlocale=en-US&amp;redirectslug=Error+loading+web+sites" rel="nofollow">Websites don't load - troubleshoot and fix error messages</a>
</p><p>http://kb&#46;mozillazine&#46;org/Error_loading_websites
</p><p><a href="https://support&#46;mozilla&#46;org/en-US/kb/what-does-your-connection-is-not-secure-mean" rel="nofollow">What do the security warning codes mean</a>
</p>