A DNS cache is a temporary database that Windows maintains in order to maintain a record of all your recent visits and attempts to visits websites, domains, and other Internet locations.
This is done to speed up name resolution, which is the process of converting a website name into an IP address that your web browser can connect to. DNS, or Domain Name System, is an index of all public websites and their corresponding IP addresses.
But if an IP address of a website changes before your DNS resolver cache updates, you will not be able to load the webpage, and Windows will show you a Page Not Found error.
If you know you are connected to the Internet correctly, and are still getting this error, then flushing your DNS cache will have your computer request new and updated information. This usually takes care of these connectivity issues.
The process is as simple as it can be.
1. Open a Command Prompt by typing cmd in the Start Menu.
2. Enter ipconfig /flushdns in the window.
Windows 10 will flush the DNS information that is stored in the cache, and will start fresh, requesting the IP addresses of all websites that you connect to.