We understand that there is an error page for a website you are trying to access that's titled "Your connection is not secure". The article [[What does "Your connection is not secure" mean?]] includes steps you can follow. However it seems a little more troubleshooting is needed to help resolve this thread. Follow the steps below to collect the Certificate Error troubleshooting information. Note: Please be aware that the certificate keychain may or may not be unique. If this is a self-signed certificate please take note to remove the information below "--BEGIN CERTIFICATE" #From the error page pictured below look for the error message.<br>[[Image:Your connection is not secure page|width=500]] #Click on the "Advanced" button and it will show the error link.<br>[[Image:Your Connection is not Secure Advanced page|width=500]] #Click on the error link and you will be taken to a page that you can copy the error text to the clipboard. The image below has blocked out the certificate for this example.<br>[[Image:Certificate error chain|width=500]] Other resources to compare errors: [https://badssl.com/] <!--Note to add the next steps for troubleshooting if they need to speak to the security team about the cert list in the privacy lists if this is not helpfuL [https://blog.mozilla.org/security/2016/01/06/man-in-the-middle-interfering-with-increased-security/] Phasing out of SHA-1 or victims of man in the middle attacks-->

Could you please provide more detail? You can open the Certificate Manager and go to the "Servers" tab. *Options/Preferences -> Privacy & Security -> Certificates: View Certificates -> Servers: "Add Exception" *paste the URL of the website (https://xxx.xxx) in it's location field. Let Firefox retrieve the certificate -> "Get Certificate" *click the "View" button and inspect the certificate You can see detail like the issuer of the certificate and intermediate certificates in the Details tab.