How to Fix a Windows Security Certificate Warningby Michael Butler ; Updated September 28, 2017
Sometimes when attempting to visit a secure website on your Windows computer, you will receive a message about a security certificate error. You will have the option of whether to continue to the site. Secure websites, such as an online bank or retail store, use security certificates so your browser knows that any financial or personal information you enter on the website will go the correct place securely. Every error message does not necessarily indicate a security problem on the website.
Check your computer's date and time. If they are incorrect, you will receive security certificate errors. Click on the time in your taskbar, and set the correct time in the pop-up window. Refresh the website where you received the error message. If you receive a security certificate error message again, the problem lies with the website's security certificate.
Click the icon that looks like a padlock next to your browser's address bar.
Read the information in the window. This will detail who owns the website, the site's verification status and any known information about the website's trustworthiness. Compare this to what you know about the site you were attempting to visit.
Click "View Certificates, then "Install Certificates."
Click "Yes" at the security warning to install the certificate for the website.