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when I activate firefox I get this message "TypeError: Components.classes[cid] is undefined" Why?

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  • Last reply by cor-el

Hand.dnc
Hand.dnc
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As soon as I activate Firefox I get a pop-up with that message and an OK button which has to be pressed before the program continues.

I am running Windows XP and Firefox 3.6 on an Acer Laptop.

As soon as I activate Firefox I get a pop-up with that message and an OK button which has to be pressed before the program continues. I am running Windows XP and Firefox 3.6 on an Acer Laptop.

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

  • Don't make any changes on the Safe mode start window.

See:

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")