If you can't inspect the certificate via "I Understand the Risks" then try this:

Open the "Add Security Exception" window by pasting or typing this URI in the Firefox location/address bar and check the certificate:

• chrome://pippki/content/exceptionDialog.xul

In the location field of this window type or paste the URL of the website.

• retrieve the certificate via the "Get certificate" button
• click the "View..." button to inspect the certificate in the Certificate Viewer

You can inspect details like the issuer and the certificate chain in the Details tab of the Certificate Viewer. Check who is the issuer of the certificate. If necessary then you can attach a screenshot that shows the certificate viewer.

There is security software like Avast and Kaspersky that intercept secure connections and send their own certificate.

ClayL said

I get an error message saying Facebook's certificate is bad and it won't allow me to set an exception. I cam sign in using Chrome with no problem but want to use FireFox.

Kapersky is the problem. Closing it allows me to log in to Facebook. Now to the Kaperksy site to see how to fix it.

Kapersky had me open Kapersky and go to" tools/settings/additional/network and check "Do not scan encrypted connections" " That reduces the level of protection but does solve the problem.

Hi

Have this problem on my sons win 10 computer with family safety and when i look at the certificate the issuer is Microsoft Family Safety but i can't find anywhere to remove any sort of limit in family safety control panel.

How to fix this?

It works fine to access facebook with Internet Explorer? :\ But who wants that? :)

PS

I tried the above but when i click on accept or something it closes the tab i'm in and it still does not work after that.

If you are on Windows 10 then you can check for issues with Microsoft Family Safety.

• http://windows.microsoft.com/en-us/windows-10/turn-off-microsoft-family-settings
• https://support.microsoft.com/en-us/kb/2965142

cor-el said

If you are on Windows 10 then you can check for issues with Microsoft Family Safety.

• http://windows.microsoft.com/en-us/windows-10/turn-off-microsoft-family-settings
• https://support.microsoft.com/en-us/kb/2965142

Hi and thanks, ive seen them and i was looking for a bit less hassle solution. Have Microsoft done this to Firefox users on purpose?

He can use Explorer for now until they fix this.