ZoneAlarm Free Firewall is an application for Windows that can control which programs on your computer can connect to the internet. If you experience connection problems with Firefox and use ZoneAlarm Free Firewall, ZoneAlarm may be blocking Firefox. This article describes how to configure the ZoneAlarm Free Firewall to allow Firefox to access the Internet.
Open the Windows Start menu, select All Programs, then select ZoneAlarm, and then select ZoneAlarm Security. The ZoneAlarm window will appear.
On the left side of the ZoneAlarm window, click Program Control.
Underneath Program Control, click Programs.
Right-click on Firefox and select Remove.
Click Yes when prompted to remove Firefox from the list.
Click Add. The Add Program window will appear.
Navigate to the Firefox installation folder (e.g. C:\Program Files\Mozilla Firefox\) and select firefox.exe. Then click Open.
Ensure that Firefox has a green check mark for each each category in the list - Access-Trusted, Access-Internet, Server-Trusted, Server-Internet: click on the ? icon for each category, and then select Allow.