With App-V prior to version 5 it was not possible to set a virtualized Firefox as the default browser. This is by design. With App-V 5.0 this is not restricted anymore.

This article applies to any Firefox version, but has been written with Firefox 17. 

  • Install the AppV 5.0 Sequencer on a workstation with Windows 7 with SP1.

  • Sequence Firefox 17.0.1 with the default settings. Only the update service should be disabled.

  • Install the AppV 5.0 Client on a second workstation with Windows 7 with SP1.

  • Install the virtualized Firefox 17.0.1. with PowerShell:
    Set-ExecutionPolicy -ExecutionPolicy Unrestricted
    Import-Module AppVClient
    Add-AppvClientPackage –Path D:\Mozilla_Firefox_17.0.1-AppV5.0_ENG\Mozilla_Firefox_17.0.1-AppV5.0_ENG.appv -DynamicDeploymentConfiguration D:\Mozilla_Firefox_17.0.1-AppV5.0_ENG\Mozilla_Firefox_17.0.1-AppV5.0_ENG_DeploymentConfig.xml | Publish-AppvClientPackage -Global
  • Start Firefox 17.0.1 and made it the default browser.

  • Go to ‘Default Programs’ in the Control Panel

  • Set Firefox as the default program:

  • In the Search box enter the webpage to open: www.google.com.

  • The icon is a ‘firefox’ one.

  • And Google is opened with Firefox.

You can only set a virtualized Firefox as the default browser if it has been published globally.