Where did you install Firefox from? Help Mozilla uncover 3rd party websites that offer problematic Firefox installation by taking part in our campaign. There will be swag, and you'll be featured in our blog if you manage to report at least 10 valid reports!

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

Lolu chungechunge lwabekwa kunqolobane. Uyacelwa ubuze umbuzo omusha uma udinga usizo.

The following keeps popping up before firefox will load, Exc in ev handl: TypeError: this.oRoot.enable is not a function

more options

There is a pop up box, it says,"Exc in ev handl: TypeError: this.oRoot.enable is not a function" It pops up before Firefox will load, what is it?

There is a pop up box, it says,"Exc in ev handl: TypeError: this.oRoot.enable is not a function" It pops up before Firefox will load, what is it?

All Replies (4)

more options
more options

Hi, I have that version, but did a fresh download anyway, still getting the pop-up, thanks though!

more options

Troubleshooting extensions and themes

Check and tell if its working.

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.