Flush DNS of malicious domain/IP:

C:\> ipconfig /flushdns

Flush NetBios cache of host/IP:

C:\> nbtstat -R

Add new malicious domain to hosts file, and route to localhost:

C:\> echo 127.0.0.1 <MALICIOUS DOMAIN> >>
C:\Windows\System32\drivers\etc\hosts

Check if hosts file is working, by sending ping to 127.0.0.1:

C:\> ping <MALICIOUS DOMAIN> -n 1