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When I launch Firefox 4.0 I get the following message "TypeError: Components.classes[cid]is undefined. How do I fix this?

  • 1 reply
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  • Last reply by TonyE

bhafen
bhafen
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When I click "ok" the pop up window clears and FireFox opens. I believe this error is also preventing Privacy Protect from activating in FireFox.

When I click "ok" the pop up window clears and FireFox opens. I believe this error is also preventing Privacy Protect from activating in FireFox.

All Replies (2)

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

bhafen
bhafen Question owner
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I determined one of the security programs was not compatible with Firefox 4.0. After disabling the program Firefox 4.0 works just fine.