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After upgrading to v 4.0.1 I get an error message on startup: "whathappened:TypeError:Components.classes['@mozilla.org/extensions/manager;1'] is undefined". I click OK and Firefox starts, but how do I get rid of the error message?

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  • Last reply by Xircal

iancb99
iancb99
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Add-ons in use: DownThemAll Download Helper Ant Video Downloader FoxySpider all of which continue to function ok with the new version.

Add-ons in use: DownThemAll Download Helper Ant Video Downloader FoxySpider all of which continue to function ok with the new version.

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Xircal
Xircal
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You'll get this error if you have an add-on installed which is incompatible with the current version of Firefox.

Try running Firefox in Diagnose Firefox issues using Troubleshoot Mode. If it functions properly in that configuration, then one of your add-ons is the culprit.

N.B. Update VLC player via http://www.videolan.org/ Your installation is seriously out of date which poses a security risk. See VLC Media Player 1.1.9 closes security holes

Actually, 1.1.9 is also a security risk, but not as bad as the version you have. See A new security flaw hits VLC

I'd advise you to install Secunia's free Personal Software Inspector, download from http://secunia.com/vulnerability_scanning/personal/ to ascertain what else you need to take care of.

Modified by Xircal