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I received following mess: What happened: type error.components.classes('@mozilla.org/extensions/manager,1') is undefined. Screen then goes white.

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jimcolloton
jimcolloton
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I have deleted and reloaded Fox 4 but still come up with same message. When I click OK to mess I come up briefly with a title bar that then rolls up and leaves me with a white screen. I have to cancel task to get out of it.'

'''I have deleted and reloaded Fox 4 but still come up with same message. When I click OK to mess I come up briefly with a title bar that then rolls up and leaves me with a white screen. I have to cancel task to get out of it.'

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cor-el
cor-el
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Delete the files extensions.* (extensions.sqlite, extensions.rdf, extensions.cache, extensions.ini) and compatibility.ini in the Firefox profile folder to reset the extensions registry. New files will be created when required.

See "Corrupt extension files": http://kb.mozillazine.org/Unable_to_install_themes_or_extensions

If you see disabled, not compatible, extensions in "Tools > Add-ons > Extensions" then click the Tools button at the left side of the Search Bar to do a compatibility check.

You may also need to check for problems with the preferences:

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