Flushing the DNS cache on Windows 10 is a very easy process and may be needed to connect to web sites that have changed servers. Due to system security permissions, you must ensure that you run the command prompt as an administrator user.

Here is how:

Ensure that you’re on the Windows 10 desktop.
Right click on the start menu and choose Command Prompt (Admin) from the menu.
Type in the command;

ipconfig /flushdns