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Recently, whenever I try to open Firefox, I get a dialog box: Exc in ev handl: TypeError: brw is undefined (JavaScript Application). Firefox is definitely my default browser

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  • 14 have this problem
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  • آخر ردّ كتبه matthew1935

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Question Recently, whenever I try to open Firefox, I get a dialog box: Exc in ev handl: TypeError: brw is undefined (JavaScript Application). Firefox is definitely my default browser. After clicking OK Firefox opens.

Question Recently, whenever I try to open Firefox, I get a dialog box: Exc in ev handl: TypeError: brw is undefined (JavaScript Application). Firefox is definitely my default browser. After clicking OK Firefox opens.

الحل المُختار

You can probably get rid of it by disabling McAfee Site Advisor ending Firefox and then restarting Firefox, and re-enabling McAfee Site Advisor, ending Firefox and restarting Firefox. But it would probably be better to uninstall Site Advisor and reinstall (as opposed to the update)...

Please see solution in http://kb.mozillazine.org/Problematic_extensions for "McAfee Site Advisor".

(Windows): For best results you should uninstall McAfee Site Advisor from Control Panel > add/change programs (Programs and Features). Reboot the system. Then Reinstall from http://www.siteadvisor.com/ and reboot the system. When installing refuse other suggested (crapware) applications.


Please mark "Solved" one answer that will best help others with a similar problem -- hope this was it.

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الحل المُختار

You can probably get rid of it by disabling McAfee Site Advisor ending Firefox and then restarting Firefox, and re-enabling McAfee Site Advisor, ending Firefox and restarting Firefox. But it would probably be better to uninstall Site Advisor and reinstall (as opposed to the update)...

Please see solution in http://kb.mozillazine.org/Problematic_extensions for "McAfee Site Advisor".

(Windows): For best results you should uninstall McAfee Site Advisor from Control Panel > add/change programs (Programs and Features). Reboot the system. Then Reinstall from http://www.siteadvisor.com/ and reboot the system. When installing refuse other suggested (crapware) applications.


Please mark "Solved" one answer that will best help others with a similar problem -- hope this was it.

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Thanks for this. I uninstalled McAfee SA then restarted. No problem. Then I reinstalled MSA and the problem reoccurred so I have uninstalled McAfee SA again and so far things are fine. It may be conflicting with something else.

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Doesn't work out for me either, so I keep it disabled, because it slows down the searches, and it won't stream its additions onto the pages after the first page of search results. Streaming or page zipping allows me to scroll down to the next page of search results without selecting the page number.

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This advice is extremely helpful. I had no clue to the solution of this problem. The only solution that I could think of was to uninstall FireFox and permanently from my computor. Thank You!