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Getting error message when Firefox starts

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  • Last reply by cor-el

creativetouch
creativetouch
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I am getting the following message when I start Firefox ever since I upgraded to the newest version (4.0.1). This is what it says:

what happened: TypeError: Components.classes[@mozilla.org/extensions/manager;1’] is undefined

Firefox doesn’t load until I click the OK button in the message. What is causing this?

I am getting the following message when I start Firefox ever since I upgraded to the newest version (4.0.1). This is what it says: what happened: TypeError: Components.classes[@mozilla.org/extensions/manager;1’] is undefined Firefox doesn’t load until I click the OK button in the message. What is causing this?

All Replies (1)

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

If it does work in Safe-mode then disable all extensions and then try to find which is causing it by enabling one at a time until the problem reappears.

  • Use "Disable all add-ons" on the Safe mode start window to disable all extensions.
  • Close and restart Firefox after each change via "File > Exit" (Mac: "Firefox > Quit"; Linux: "File > Quit")

In Firefox 4 you can use one of these to start in Safe mode:

  • Help > Restart with Add-ons Disabled
  • Hold down the Shift key while double clicking the Firefox desktop shortcut (Windows)