Online Armor Free is a software package for Microsoft Windows. It includes a firewall component, which controls which programs can access the outside world. If Online Armor Free is not set to fully allow Firefox, Firefox will be unable to connect to websites and may generate "Servidor no encontrado" errors.

This article describes how to configure Online Armor Free to give Firefox access to the Internet.

1. Close Firefox by going to the File menu and selecting Exit.
2. Double-click the Online Armor icon in the system tray.
   
3. Click Firewall on the left side.
4. The status under Firefox should be Allowed.
   

If Firefox is not listed:

1. Click Add.
2. Find Firefox.exe. By default it is located in C:\Program Files\Mozilla Firefox.
3. Click Open and make sure the status is Allowed.