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How do I rectify the error - A new window does not open unless I click 'ok' on the error box which says 'Java Script Application'; What happened:type Error; Components.Classes['@mozilla.org/extensions/manager;1'] is undefined

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  • Last reply by cor-el

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Whenever I try and open a new firefox window (not ta), or a site automatically opens one, the new window does not open unless I click OK or close the dialog box 'x'

The dialog box has a headinf -Java Script Application and the message is

What happened:type Error; Components.Classes['@mozilla.org/extensions/manager;1'] is undefined

Whenever I try and open a new firefox window (not ta), or a site automatically opens one, the new window does not open unless I click OK or close the dialog box 'x' The dialog box has a headinf -Java Script Application and the message is What happened:type Error; Components.Classes['@mozilla.org/extensions/manager;1'] is undefined

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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: Tools > Add-ons > Appearance/Themes).

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)

See:

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")