If you see SEC_ERROR_REUSED_ISSUER_AND_SERIAL warning in your Firefox browser, then you need to take a few steps to resolve the issue.

Firefox: 'Secure Connection Failed' to Microsoft.com When using Firefox, accessing microsoft.com is not working quite as expected for many around the world.

How do I fix Secure Connection Failed in Firefox? Secure Connection Failed is one of the common problems on Firefox & in order to troubleshoot, we need to understand the type of connection errors ...