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On starting firefox 4 I get the following message: "What happened:Type Error: component classes['Mozilla.org/extensions/manager; 1'] is undefined." The program otherwise works well. What should I do?

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  • Last reply by TonyE

Moncayo@238
Moncayo@238
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The complete message, besides what I quoted, includes a yellow warning triangle and, on top, the indication that it is a "Java Script Application" problem (0r so I understand the total rectangle in which the message appears.

The complete message, besides what I quoted, includes a yellow warning triangle and, on top, the indication that it is a "Java Script Application" problem (0r so I understand the total rectangle in which the message appears.

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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