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firefox is useless - says EVERY site has bad certificate - even MOZILLA will not load
The owner of mozilla.com has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website.
The owner of www.google.com has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website.
The owner of www.msn.com has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website.
Chosen solution
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
Read this answer in context 👍 0All Replies (2)
Hi, sounds like some corruption in a file. Please : uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :
- https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles
- https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer
Reinstall with Current Release Firefox 59.0.2 with a Full Version Installer
Please let us know if this solved your issue or if need further assistance.
Chosen Solution
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