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Everytime I open Firefox I get this message: what happened:TypeError: Components.classes['@mozilla.org/extensions/manager;1'] is undefined

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  • Last reply by TonyE

Fiddlescratcher
Fiddlescratcher
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Every time I open Firefox I get the following message window: what happened:TypeError: Components.classes['@mozilla.org/extensions/manager;1'] is undefined

I click on OK and then Firefox opens.

Every time I open Firefox I get the following message window: what happened:TypeError: Components.classes['@mozilla.org/extensions/manager;1'] is undefined I click on OK and then Firefox opens.

All Replies (1)

TonyE
TonyE
  • Moderator
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This indicates that an add-on that you are using is not compatible with Firefox 4. For details of how to troubleshoot that see https://support.mozilla.com/kb/Troubleshooting+extensions+and+themes