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Upon launch of Firefox, get the following error message: Java Script Application, Type Error: Components, Classes [cid] is undefined. How can I resolve this problem?

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  • Last reply by TonyE

Pawpatch
Pawpatch
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Upon launching Firefox 4, I get a Java Script Application pop-up window error message. The window notes: Type Error: Components, Classes [cid] is undefined.

Already checked to see if my Java was up to date and it is. Did not have this problem with the previous version of Firefox. How do I resolve this problem?

Upon launching Firefox 4, I get a Java Script Application pop-up window error message. The window notes: Type Error: Components, Classes [cid] is undefined. Already checked to see if my Java was up to date and it is. Did not have this problem with the previous version of Firefox. How do I resolve this problem?

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TonyE
TonyE
  • Moderator
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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