You need to open a command prompt.

For Windows XP and earlier:

To do this, click "Start", there select "Run" and enter there is a word cmd then press Enter.

You will see command prompt Windows. There, type the following: ipconfig /flushdns and press Enter (you can copy, not to write by hand - then copy the command prompt, right-click paste).

If you see the following:

"IP configuration for Windows
Successfully flushed the DNS resolver cache."

So the DNS cache cleared. You can close the command prompt.

For Windows Vista, Windows 7, Windows 8 and Windows 10:

To do this, click "Start", there select "Run" and enter there is a word cmd then press Enter. Found the cmd program, run it.

You will see command prompt Windows. There, type the following: ipconfig /flushdns and press Enter (you can copy, not to write by hand - then copy the command prompt, right-click paste).

If you see the following:

"IP configuration for Windows
Successfully flushed the DNS resolver cache."

So the DNS cache cleared. You can close the command prompt.