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

How can I cure/stop this error message on startup 'Exc in ev handl: TypeError: this.oRoot.enable is not a function'

  • 2 cavab
  • 9 have this problem
  • 16 views
  • Last reply by GowerMick

more options

When starting Firefox 8.0, I get the above JavaScript Application error. When I click 'OK' in dialogue box, Firefox appears to start normally.

What could be the cause, and how can I cure it?

When starting Firefox 8.0, I get the above JavaScript Application error. When I click 'OK' in dialogue box, Firefox appears to start normally. What could be the cause, and how can I cure it?

Chosen solution

This issue can be caused by the McAfee Site Advisor extension

Start Firefox in Safe Mode to check if one of the extensions is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).

   Don't make any changes on the Safe mode start window.
Read this answer in context 👍 2

All Replies (2)

more options

Seçilmiş Həll

This issue can be caused by the McAfee Site Advisor extension

Start Firefox in Safe Mode to check if one of the extensions is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).

   Don't make any changes on the Safe mode start window.
more options

Hi Swarnava,

I thought I had already disabled this extension, but when I checked the list, and despite it being marked as disabled, the 'Disable' button was still active!!! I clicked the disable button yet again, it then changed to 'Enable'. I restarted Firefox, et voila, nasty little message was no more.

Many Thanks

Modified by GowerMick