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I keep getting this error message and Firefox won't start....Exc in ev handl: Error: Error setting property on NPObject!

jch3113
jch3113
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Firefox won't start and this message keeps coming up....I uninstalled and reinstalled....but didn't help...

Exc in ev handl: Error: Error setting property on NPObject!

Firefox won't start and this message keeps coming up....I uninstalled and reinstalled....but didn't help... Exc in ev handl: Error: Error setting property on NPObject!

Chosen solution

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.
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All Replies (1)

David McRitchie
David McRitchie
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Chosen Solution

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.