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Why does Firefox now block many websites, starting today?
I get an error message "Your connection is not secure
The owner of ______________ has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website."
This has not happened in the past. I have used the same Kaspersky security software and settings for several years. I worry about following your advice and no longer scanning encrypted connections and thereby lessening my protection.
All Replies (5)
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
Why did this start happening today, out of the blue with no warning? Are you saying that I am not going to be less safe online if I follow your troubleshooting advice?
Hi PeterMartinGlenthorne, do you want to start by confirming the source of the issue?
Click the Advanced button to show the technical details of Firefox's objections, and you can copy/paste those here.
If you do have the SEC_ERROR_UNKNOWN_ISSUER code, could you click that to see whether Firefox will display the certificate details (large block of gibberish) that you can paste into a reply?
Hi PeterMartinGlenthorne, could you check another thing, based on another thread (certificate problem / SSL Error with Firefox 58.0.1 (64-Bit) Kaspersky Internet Security 17.0.0.611 and active FF Master PW).
Open Firefox Certificate Manager using
- Windows: "3-bar" menu button (or Tools menu) > Options
- Mac: "3-bar" menu button (or Firefox menu) > Preferences
- Linux: "3-bar" menu button (or Edit menu) > Preferences
- Any system: type or paste about:preferences into the address bar and press Enter/Return to load it
In the search box at the top of the page, type cert and Firefox should filter to the "Certificates" section. Click the "View Certificates" button.
In the Certificate Manager, click the Authorities mini-tab. This is going to have a very long list. Can you find the Kaspersky certificate here (under Kaspersky Lab or other Kaspersky affiliate)?
If you have that certificate stored, click it and then click the "Edit Trust" button. Is the first box checked -- "This certificate can identify web sites"?
Thank you very much for the detailed response. I am now away from home for 2 weeks and my computer will be turned off. I'll read your advice in detail and try to understand what has happened when I return home. So, I'm not ignoring you and do appreciate your response to my troubles. I'll get back to you later this month. Regards, PeterMartinGlenthorne