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I am using FoxTester to run firefox 3.6 to test my development site on non-html5 browsers.

It used to work fine for week until suddenly when try to launch 3.6 it will try to install an update (presumably firefox 16), but fails. As a result I cannot launch 3.6 at all.

How do I stop firefox from running auto-update?

I had a look at the mozilla support site here and seen many other forums suggesting the same. The thing is though that I cannot get to those settings as I cannot launch firefox 3.6 to disable auto-update as the auto-update prevents me from launching it.

Is there a configuration file where I can disable auto update or a launch parameter?

share|improve this question
Why don't you simply install an even earlier version? You could always compile Firefox 3.6 yourself and disable the check. – Ramhound Jun 22 '12 at 11:13
@Ramhound wow! compile firefox, that's overkill – vikki Jun 22 '12 at 13:39
@Ramhound well I was already struggling to find a version as old as 3.6 and I don't think what compiling would be necessary. – d_inevitable Jun 22 '12 at 22:52
up vote 2 down vote accepted
  • Look in your profile directory.
    (Where your profile directory is, depends on your operating system and version. Note: it might be in a hidden directory).
  • Open the file prefs.js
  • If it has a line saying
    user_pref("app.update.enabled", true);
    change the true to false.
  • Otherwise, add a new line saying
    user_pref("app.update.enabled", false);
    Note: the lines probably need to be in alphabetical order, so make sure you insert it in the right position.

Hope this helps!

share|improve this answer
+1 for teaching me something new. – Nima Jun 22 '12 at 13:37
Well, it is a last resort. Normally it's not recommended to edit the prefs.js directly (since you can change all the prefs by going to about:config) but if you can't start up the browser because of a setting that needs to change, you can do that. – Mr Lister Jun 22 '12 at 13:45

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