reading/writing preferences
I have read most all of the documentation and questions related to preferences I could find but I have an error that is always coming up no matter what method I try and I do not understand it.

js file loaded in browser overlay xul

    var prefs = Components.classes["@mozilla.org/preferences-service;1"].
					getService(Components.interfaces.nsIPrefService).
					getBranch("extensions.{my-guid-id}.");
		
    var value = prefs.getBoolPref("firstrun");

defaults/preferences/prefs.js:    

    pref("extensions.{my-guid-id}.firstrun", true);


The error message in the error console says `uncaught exception: "compenent returned failure code 0x8000ffff" on  line 27` which is right at `getBoolPref()` call.

reading/writing preferences
===

I have read most all of the documentation and questions related to preferences I could find but I have an error that is always coming up no matter what method I try and I do not understand it.

js file loaded in browser overlay xul

    var prefs = Components.classes["@mozilla.org/preferences-service;1"].
					getService(Components.interfaces.nsIPrefService).
					getBranch("extensions.{my-guid-id}.");
		
    var value = prefs.getBoolPref("firstrun");

defaults/preferences/prefs.js:    

    pref("extensions.{my-guid-id}.firstrun", true);


The error message in the error console says `uncaught exception: "compenent returned failure code 0x8000ffff" on  line 27` which is right at `getBoolPref()` call.
