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On startup I get error msg: BRW is undefined

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When I start Firefox I get the error message: "Exc in ev handl: TypeError: brw is undefined" and sometimes FireFox fails to open. When it does open it is to a blank page not my home page. When I click on the Home button my correct Home page opens. I have updated my version of Java with no effect on this error.

When I start Firefox I get the error message: "Exc in ev handl: TypeError: brw is undefined" and sometimes FireFox fails to open. When it does open it is to a blank page not my home page. When I click on the Home button my correct Home page opens. I have updated my version of Java with no effect on this error.

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Try the Firefox SafeMode to see how it works there.
A troubleshooting mode, which disables most Add-ons.
(If you're not using it, switch to the Default Theme.)

  • You can open the Firefox 4/5/6/7 SafeMode by holding the Shft key when you use the Firefox desktop or Start menu shortcut.
  • Or use the Help menu item, click on Restart with Add-ons Disabled... while Firefox is running.

Don't select anything right now, just use "Continue in SafeMode."

To exit the Firefox Safe Mode, just close Firefox and wait a few seconds before using the Firefox shortcut (without the Shft key) to open it again.

If it is good in the Firefox SafeMode, your problem is probably caused by an extension, and you need to figure out which one.
http://support.mozilla.com/en-US/kb/troubleshooting+extensions+and+themes