Steps to reset Firefox successfully:

• To get more troubleshooting information, go to the menu button, choose Help, and then More Troubleshooting Information.
• In the confirmation window that appears, click Refresh Firefox, then Refresh Firefox again. Firefox will close in order to reload its cache.
• When you're done, a window will appear with a list of the data you've imported. Finish by pressing the Finish button. Firefox will startup.
• Select whether you want all or some of your windows and tabs to be restored, then click the Let's go! button.
• If you can't start Firefox normally, use the Refresh Firefox button in the Firefox Troubleshoot Mode box. You can also perform a manual refresh by creating a new profile and moving your critical data to it.

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