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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
more options

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.
Read this answer in context 👍 5

All Replies (1)

David McRitchie
David McRitchie
more options

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.