Open the firewall console by right-clicking the system tray icon representing NPF and select Settings, or select Norman Personal Firewall from the Programs section of Windows’ Start menu.

Click the “Turn Engine Off" button if you stop NPF. When the firewall is stopped, the text on this button will change to “Turn Engine On".

An example of a situation where you may want to temporary stop the firewall is if you want to check if the firewall is blocking connections that you want to allow. In this case you should also have a look at the answer to the question “I think I have allowed/denied something by mistake, how can I check this?"