hi jimjobson, in case this is happening in an enterprise environment, please tell this to your it staff since the pre-built configuration they are using for firefox is probably failing. if not, then please manually delete the firefox installation directory and then reinstall the browser from https://www.mozilla.org/en-US/firefox/all/.

This did not work for me. I initially installed FF 52.5.2 ESR on a Windows 7 Pro machine using the Microsoft Deployment Toolkit MDT). I then added the local-settings.js file to the \defaults\pref folder and the mozilla.cfg file to the Mozilla Firefox install directory. I received the error message "Failed to read the configuration file..."

I uninstalled FF and manually deleted the install directory. I reimaged the workstation and added FF again using MDT. I manually copied the files. Got the error message again.

I had copied the JS and CFG files off a web site so I manually recreated these files... and get the same error.

I again uninstalled FF and manually deleted the install folder. I then ran the 52.5.2 ESR setup file manually. And again copied the JS and CFG files to the appropriate locations and, again, got the error message.

I installed Windows 7 Pro from scratch (dvd), then installed FF 55.2.5 ESR and copied the JS and CFG files over to the appropriate locations and still get error message.

I tried the 32- and 64-bit versions and got the same result.

Now the error message is kind of ironic ("Please contact your system administrator.") since I AM the system administrator.

Here are the contents of my files:

local-settings.js:

// Where is the config file?! pref("general.config.filename", "TestMoz.cfg"); pref("general.config.obscure_value", 0);

TestMoz.cfg:

// Any comment. You must start the file with a comment! // Disable updater lockPref("app.update.enabled", false); // make absolutely sure it is really off lockPref("app.update.auto", false); lockPref("app.update.mode", 0); lockPref(app.update.service.enabled", false);

Thanks in Advance for your help.

OregonSteve "Never, never doubt what nobody is sure about." -Willy Wonka

[SOLVED]

Didn't see a typo (missing double quote) Didn't know\realize that one bad line would make the entire file ineffective.

Thanks

OregonSteve "Never, never doubt what nobody is sure about," -WIlly Wonka

Keep in mind that the mozilla.cfg file or like you named it is run as privileged JavaScript code and any error in this file will throw an exception and abort the execution.