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running firefox 4.0.1 & have window popup that says JavaScript Appl. uninstal set. Can this be fixed?

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Yesterday I upgraded Firefox on my desktop to 4.0.1...ever since, I get a popup window that says ....JavaScript Application and below in the window uninstal set....followed by a ok button to click. I could use some help on this. Thanks.

Yesterday I upgraded Firefox on my desktop to 4.0.1...ever since, I get a popup window that says ....JavaScript Application and below in the window uninstal set....followed by a ok button to click. I could use some help on this. Thanks.

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This issue can be caused by an extension 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)