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what happened:.... this is the popup message TypeError: Components.classes['@mozilla.org/extensions/manager;1'] is undefined

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  • 84 have this problem
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  • Last reply by cor-el

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Just upgraded to Version 5 - same problem.


" TypeError: Components.classes['@mozilla.org/extensions/manager;1'] is undefined"


This is the popup message I get when starting up Firefox. When I ok or kill the popup Firefox seems to work. This problem started when I upgraded the Windows 7 and install the latest Firefox (version 4 I think) about two months ago. Occurs on both the desktop and laptop. Any suggestions? Thanks

Just upgraded to Version 5 - same problem. " TypeError: Components.classes['@mozilla.org/extensions/manager;1'] is undefined" This is the popup message I get when starting up Firefox. When I ok or kill the popup Firefox seems to work. This problem started when I upgraded the Windows 7 and install the latest Firefox (version 4 I think) about two months ago. Occurs on both the desktop and laptop. Any suggestions? Thanks

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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).