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 [https://support.mozilla.org/en-US/kb/websites-dont-load-troubleshoot-and-fix-errors?redirectlocale=en-US&redirectslug=Error+loading+web+sites Websites don't load - troubleshoot and fix error messages] 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

''jerdoggmckoy [[#question-1240158|said]]'' <blockquote>... give me this insecure connection error. </blockquote> Click on the Advance and expand it so there is a certificate information that looks like a bunch of letters and such. Post that in chat so somebody can decode it and tell you what software is likely doing this. It is likely say a antivirus client inserting its own man in middle certificate if you have feature enabled in the client.