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Before starting, receive following message "Exc in ev handl: This .0root.enable is not a function", what does this mean

  • 3 respostas
  • 3 have this problem
  • 5 views
  • Last reply by janiserj

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Before starting Mozilla Firefox ( MF )and after pressing start, a message box appears on the screen: Message

              Exc in ev handl:This .0root. enable is not a function

When I press the Enter Key MF starts and everyhing appears to be functioning okay. MF will not start until I press the Enter Key. Why!!!!bold text

Before starting Mozilla Firefox ( MF )and after pressing start, a message box appears on the screen: Message Exc in ev handl:This .0root. enable is not a function When I press the Enter Key MF starts and everyhing appears to be functioning okay. MF will not start until I press the Enter Key. Why!!!!'''bold text'''

Chosen solution

Add-ons are the responsibility of their authors. McAfee does not even put their extension on http://addons.mozilla.org you had to install it from their site.

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 (3)

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This issue can be caused by the McAfee Site Advisor extension


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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Chosen Solution

Add-ons are the responsibility of their authors. McAfee does not even put their extension on http://addons.mozilla.org you had to install it from their site.

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.

David McRitchie modificouno o

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Thanks to "dmcritchie" for solving my problem and to all others who Helped me. Problem solved and I really appreciate it, Thanks again.

janiserj