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There is error message when start Firefox 4.0.1 as follow: "what happened: TypeError; Components.classes['@mozzilla.org/extensions/manager;1'] is undefined"

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  • Last reply by TonyE

tomcat
tomcat
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There is error message when start Firefox 4.0.1 as follow: "what happened: TypeError; Components.classes['@mozzilla.org/extensions/manager;1'] is undefined"

There is error message when start Firefox 4.0.1 as follow: "what happened: TypeError; Components.classes['@mozzilla.org/extensions/manager;1'] is undefined"

All Replies (1)

TonyE
TonyE
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That indicates that you are using an add-on that is not compatible with Firefox 4. For details of how to troubleshoot this to find out what one is causing the problem see https://support.mozilla.com/kb/Troubleshooting+extensions+and+themes