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I don´t get any Java Script referral on the: Exc in ev handl: Error: Bad NPObject as private data, what is then my problem?

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Exc in ev handl: Error: Bad NPObject as private data

This is the pop up that keeps annoying me in FF. You send me the question: The box that the error is in says something about JavaScript?

I´m answering NO!

Exc in ev handl: Error: Bad NPObject as private data This is the pop up that keeps annoying me in FF. You send me the question: The box that the error is in says something about JavaScript? I´m answering NO!

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This issue can be caused by an extension that isn't working properly (McAfee Site Advisor).


Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the extensions is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).

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Disable "McAfee Site Advisor" extension which was just updated to 3.4.0, which probably took it out of the addons block list.

  • "Ctrl+Shift+A" > find McAfee Site Advisor and use "Disable", and then restart Firefox.
  • Do a Google Search no problem
  • It seems that if you re-enable Site Advisor again, and restart Firefox you are okay. At least you know where to look if you get the error again or Google searches slow down.

Modified by David McRitchie