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Sccm install Firefox, now get error cant open program. Failed to read the configuration file. Please contact your system administrato

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  • Last reply by cor-el

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I used a script to install it from this site. https://www.itsupportguides.com/configmgr-sccm/install-and-configure-firefox-silently/

I followed the instructions exactly as it on that site now none of my users can use firefox. they get the failed to read config file and program doenst launch.

I used a script to install it from this site. https://www.itsupportguides.com/configmgr-sccm/install-and-configure-firefox-silently/ I followed the instructions exactly as it on that site now none of my users can use firefox. they get the failed to read config file and program doenst launch.

Chosen solution

You get this error message when there is a .js (local-settings.js) file in the "defaults\pref" folder that specifies to process the mozilla.cfg file, but the mozilla.cfg isn't found.

Did you make sure that the mozilla.cfg doesn't have a hidden .txt file extension?


You can use the mozilla.cfg file in the Firefox program folder to set or lock preferences and run privileged JavaScript code.

A local-settings.js file needs to be placed in the "defaults/pref" folder where also the channel-prefs.js file is located to specify using mozilla.cfg.

pref("general.config.filename", "mozilla.cfg");
pref("general.config.obscure_value", 0);

These functions can be used in the mozilla.cfg file:

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

The mozilla.cfg file needs to start with a comment line (//).

See Configuration:

See also:

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Chosen Solution

You get this error message when there is a .js (local-settings.js) file in the "defaults\pref" folder that specifies to process the mozilla.cfg file, but the mozilla.cfg isn't found.

Did you make sure that the mozilla.cfg doesn't have a hidden .txt file extension?


You can use the mozilla.cfg file in the Firefox program folder to set or lock preferences and run privileged JavaScript code.

A local-settings.js file needs to be placed in the "defaults/pref" folder where also the channel-prefs.js file is located to specify using mozilla.cfg.

pref("general.config.filename", "mozilla.cfg");
pref("general.config.obscure_value", 0);

These functions can be used in the mozilla.cfg file:

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

The mozilla.cfg file needs to start with a comment line (//).

See Configuration:

See also: