If you visit websites and Firefox doesn’t load the website, instead Firefox shows you the error message “Your connection is not secure”, “SEC_ERROR_UNKNOWN_ISSUER” then it is advisable to take the following steps in this instruction to solve the SSL (Secure Socket Layer) certificate connection problem.
Your connection is not secure error originates from a trust issue with the SSL Certificate on the website you are visiting, this your connection is not secure prevents Firefox from successfully loading the entire website.
Your connection is not secure is basically a protection against misconfigured websites in order to prevent Firefox from visiting website that may steal information by a man in the middle attack. It is complicated protection, however, the fix is usually very simple, follow instructions below to get rid of your connection is not secure errors in Firefox.
How to solve Your connection is not secure error in Firefox
Open Firefox, if you didn’t already. In the address bar type: about:config
In the warning screen, accept the risk and continue with Firefox configuration settings.
Use the Windows certificate store
In the search bar type: security.enterprise_roots.enabled
Change the boolean type from false to true by double-clicking on it. Doing so allows Firefox to trust and use the Windows Certificate Store.
Restart Firefox for the changes to take effect and see if the “your connection is not secure” error in Firefox is fixed.
Reset Firefox settings
The next step you want to perform if the problem is not solved is to reset Firefox settings.
Resetting Firefox will change all settings to default as if you had just installed Firefox, this can help you to identify the root cause of the your connection is not secure error.
After the Firefox reset you can find your old Firefox data in a folder called “Old Firefox data” on your Windows Desktop.
How to Restore old Firefox data.
In the address bar type: about:support
Click the Refresh Firefox button in the “Give Firefox a tune-up” section. Confirm the reset by clicking Refresh Firefox in the confirmation dialog.
This will: remove your add-ons and customizations and restore your browser settings to their defaults.
I hope this article has helped you fix the your connection is not secure errors in Firefox!
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