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Facebook doesn't work in Firefox 15. Any idea why?

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  • 36 have this problem
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  • Last reply by cor-el

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The Facebook login page comes up momentarily, and then is quickly succeeded by an error message: File not found Firefox can't find the file at jar:file:///C:/Program Files (x86)/Mozilla Firefox/omni.ja!/chrome/browser/content/browser/undefinedcheck6only.facebook.comajax/v6.php?v=check6only&pingonly=false. Others are having similar problems. Pretty disastrous for Firefox's reputation, I fear.

The Facebook login page comes up momentarily, and then is quickly succeeded by an error message: File not found Firefox can't find the file at jar:file:///C:/Program Files (x86)/Mozilla Firefox/omni.ja!/chrome/browser/content/browser/undefinedcheck6only.facebook.comajax/v6.php?v=check6only&pingonly=false. Others are having similar problems. Pretty disastrous for Firefox's reputation, I fear.

Chosen solution

The Facebook site worked in Safe Mode. I tried disabling addons individually: the problem seems to have been the ZoneAlarm toolbar. Firefox 15 disabled the ZoneAlarm security engine but not the toolbar. I have now disabled the ZoneAlarm toolbar. Thanks for your help.

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Start Firefox in Safe Mode to check if one of the extensions or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance/Themes).

You can check for problems with the preferences and if necessary delete the prefs.js file and a possible user.js file to reset all prefs.

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Chosen Solution

The Facebook site worked in Safe Mode. I tried disabling addons individually: the problem seems to have been the ZoneAlarm toolbar. Firefox 15 disabled the ZoneAlarm security engine but not the toolbar. I have now disabled the ZoneAlarm toolbar. Thanks for your help.

Modified by mfcayley

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You're welcome