Please read this article to see if it helps:

http://support.mozilla.com/en-US/kb/How%20to%20set%20the%20home%20page

this is good but i am actually looking to automate this in our corporate environment by using either user.js or prefs.js file. I know in past i have accomplish this through browserconfig.properties with the following content

browser.startup.homepage=http://mysite.com/ browser.startup.homepage_reset=http://mysite.com/

Sorry, I am not very experienced in configuring the "js" files, so I don't want to give you any wrong information. Some other experienced Firefox users here will have to help you further.

Anyone else?

You can set the home page via the Firefox user interface and copy the lines from the file prefs.js

For new users that do not have a profile you can place files in the default template location.
That folder doesn't exist anymore, so you will have to create it. All files in that folder are copied to a new profile.

• C:\Program Files\Mozilla Firefox\defaults\profile\

You can also do the configuration via a file mozilla.cfg in the main profile folder.
See:

• http://kb.mozillazine.org/Locking_preferences

You can use these functions in mozilla.cfg :

defaultPref();  // set new default value
pref(); // set pref, but allow changes
lockPref();  // lock pref, disallow changes

My Problem lies in the user.js file. FF 4 is already there on the machine & my user.js has this content in it.

user_pref("browser.startup.homepage_override.mstone", "ignore");

which basically locks down the change homepage option. I can always push the new user.js file but the problem is that profile is already there & i don't know how to change this

As you have found, Firefox 4 has introduced some significant changes to how Firefox handles the configuration files. The configuration files now reside in a package file called 'omni.jar' you can over-ride the settings by creating new configuration files and placing into the 'defaults\pref\' folder or editing and repackaging the 'omni.jar' file.

However, the 'browser.startup.homepage' is not being accepted using this method - as this is a suspected bug it has been filed with Mozilla.

After going through several other options I've devised and tested a consistent and simple way of applying the customisations to a Firefox 4 installation. There is one limitation as detailed in the instructions, it may be a good or a bad thing depending on your deployment situation and requirements. See here for more information:

http://www.mockbox.net/configmgr-sccm/300-firefox-4-set-default-home-page-for-all-users.html

This article has specific steps for creating a Firefox 4 deployment with customisation like you're looking for:

http://mockbox.net/configmgr-sccm/174-install-and-configure-firefox-silently.html

You can use a mozilla.cfg file to change the default value of prefs.

You can use these functions in mozilla.cfg:

defaultPref();  // set new default value
pref(); // set pref, but allow changes
lockPref();  // lock pref, disallow changes

See:

• http://kb.mozillazine.org/Locking_preferences