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Why am I getting this popup: TypeError:Components.Classes[cid] is undefind

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  • 6 have this problem
  • 3 views
  • Last reply by cor-el

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Downloaded FF 5.0. Now I'm getting java application popup: 'TypeError: Components.Classes[cid] is undefined'.

What's going on?????

Downloaded FF 5.0. Now I'm getting java application popup: 'TypeError: Components.Classes[cid] is undefined'. What's going on?????

All Replies (1)

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This issue can be caused by an add-on that isn't working properly.

Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the extensions is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).

If it does work in Safe-mode then disable all extensions and then try to find which is causing it by enabling one at a time until the problem reappears.

  • Use "Disable all add-ons" on the Safe mode start window to disable all extensions.
  • Close and restart Firefox after each change via "File > Exit" (Mac: "Firefox > Quit"; Linux: "File > Quit")

In Firefox 4 you can use one of these to start in Safe mode:

  • Help > Restart with Add-ons Disabled
  • Hold down the Shift key while double clicking the Firefox desktop shortcut (Windows)