Join the AMA (Ask Me Anything) with the Firefox leadership team to celebrate Firefox 20th anniversary and discuss Firefox’s future on Mozilla Connect. Mark your calendar on Thursday, November 14, 18:00 - 20:00 UTC!

This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Window pops up, (Javascript Application) EXC in ev handl: TypeError: this.oRoot.enable is not a function

  • 5 svar
  • 897 har dette problemet
  • 20 views
  • Siste svar av me123abc

more options

When connecting to Firefox a window pops up containing the following message:

(Javascript Application) Exc in ev handl: TypeError: this.oRoot.enable is not a function

When clicking OK or closing the window allows connection to Firefox Start Page.

This window does not appear when connecting to Internet Explorer

When connecting to Firefox a window pops up containing the following message: (Javascript Application) Exc in ev handl: TypeError: this.oRoot.enable is not a function When clicking OK or closing the window allows connection to Firefox Start Page. This window does not appear when connecting to Internet Explorer

All Replies (5)

more options

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).

more options

Comcast Constant Guard users have reported getting that error message, too.

more options

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.

Endret av David McRitchie

more options

Disabling the "McAfee Site Advisor" extension worked for me. Thanks!

more options

umm someone answer this pleasee. how do you Disable the "McAfee Site Advisor"?!?!?!?!?!? please answer fasttt