Check the date and time and time zone in the clock on your computer: (double) click the clock icon on the Windows Taskbar.

Check out why the site is untrusted and click the "Advanced" button to expand this section to see extra details.

You can click the "Advanced" button to expand this section and show extra details. If the certificate is not trusted because the issuer certificate is unknown (SEC_ERROR_UNKNOWN_ISSUER) then click the blue error message to expand this section and show the certificate chain. You can click "Copy text to clipboard" and paste the base64 encoded certificate chain text in a reply. That will allow us to details like the issuer of the certificate.

• https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER

• always be cautious when you get an 'Untrusted' error message
• never create a permanent exception without investigating the cause and only use this to inspect the certificate

Thanks for the prompt response Cor-el. I'm a bit puzzled since what should be ok sites like Mozilla itself or the BBC give this problem. Since it stops after a refresh I wonderif it could be add-ons? I've been trying out ones like Ad Blockers after reading the blog. Maybe add those one at a time and see what happens.

Adblockers can do that and that could be why the site says insecure because it can't track your activity on the site.

Can you post your extensions list?

• https://support.mozilla.org/en-US/kb/use-troubleshooting-information-page-fix-firefox

You can check the connection settings.

• Options/Preferences -> General -> Network: Connection -> Settings

If you do not need to use a proxy to connect to internet then try to select "No Proxy" if "Use the system proxy settings" or one of the others do not work properly.

See "Firefox connection settings":

• https://support.mozilla.org/en-US/kb/firefox-cant-load-websites-other-browsers-can

Also check for malware and adware.

• https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-caused-malware

Thanks

Firefox seems ro run fine if I don't add anything. Connection seems to be by system settings. I was trying out Ghostery and Privacy Badger. I could add one at a time and see what happens? Though Bitdefender seems to want to shut down Firefox and Opera from time to time.

Then you need a better A/V and Bitdefender isn't that one.

I'm getting an insecure site warning for every URL so am contacting you via Safari. Even Mozilla is listed as an insecure site. One answer here mentions Windows - what about Macs?!

Hi berniex822

Could you please provide more detail?

• click the "Advanced" button to show more detail
• click the blue SEC_ERROR_UNKNOWN_ISSUER message to show the certificate chain
• click "Copy text to clipboard" and paste the base64 certificate chain text in a reply

cor-el said

Hi berniex822 Could you please provide more detail?

• click the "Advanced" button to show more detail
• click the blue SEC_ERROR_UNKNOWN_ISSUER message to show the certificate chain
• click "Copy text to clipboard" and paste the base64 certificate chain text in a reply

Afraid I can't do as you ask. I made changes in Avast settings and got rid of the problem