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Failure to read configuration file because of enable_sandbox.

robert_phan

I was trying to set a local file as a new tab, and followed a guide online. I put the autoconfig.js and the firefox.cfg files all in the right place, but it didn't work. When closed and reopened the browser, it said "Failed to read the configuration file. Please contact your system administrator." I figured out that the very last line:

pref("general.config.sandbox_enabled", false);

was causing it to say that. How do I fix this?

I was trying to set a local file as a new tab, and followed a guide online. I put the autoconfig.js and the firefox.cfg files all in the right place, but it didn't work. When closed and reopened the browser, it said "Failed to read the configuration file. Please contact your system administrator." I figured out that the very last line: pref("general.config.sandbox_enabled", false); was causing it to say that. How do I fix this?

All Replies (7)

You can check the Browser Console for more detail.

The line to disable the sandbox needs to be in the autoconfig.js file in the defaults\pref folder and is mandatory if you have included JavaScript code in autoconfig.cfg. Note that autoconfig.js needs to use Unix line endings (LF and not CR/LF).

// autoconfig.js needs to start with a comment line
pref("general.config.filename", "autoconfig.cfg");
pref("general.config.obscure_value", 0);
pref("general.config.sandbox_enabled", false);

Thank you for the response. The error message no longer shows up. Unfortunately, it still doesn't work. I followed this [guide] right here. The browser console says "extension is undefined" and "this.window.gBrowserInit is undefined".

Endret av robert_phan

robert_phan said

Thank you for the response. The error message no longer shows up. Unfortunately, it still doesn't work. I followed this [guide] right here. The browser console says "extension is undefined" and "this.window.gBrowserInit is undefined".

I don't see this.window.gBrowserInit in the other thread. Do you have other code in your .cfg file?

jscher2000 said

robert_phan said

Thank you for the response. The error message no longer shows up. Unfortunately, it still doesn't work. I followed this [guide] right here. The browser console says "extension is undefined" and "this.window.gBrowserInit is undefined".

I don't see this.window.gBrowserInit in the other thread. Do you have other code in your .cfg file?

I don't think so. This is the code in my cfg file:

// var {classes:Cc,interfaces:Ci,utils:Cu} = Components; /* set new tab page */ try { Cu.import("resource:///modules/AboutNewTab.jsm"); var newTabURL = (My file); AboutNewTab.newTabURL = newTabURL; } catch(e){Cu.reportError(e);} // report errors in the Browser Console

It doesn't work. In the browser console, it said that an extension and this.window.gBrowserInit was undefined.

Oh, I see. It doesn't sound like those messages are related to your Autoconfig script.

Any difference if you set the new tab URL to a website instead of the local file? For example:

var newTabURL = 'https://support.mozilla.org/';

What file or URL do you use for the new tab page ?

You can open the file in a Firefox tab to get the correct URL.

Thank you for the tips! I've figured out the problems on my own though, and it's because I missed a semicolon lol.