• A bug with one of the Firefox programme files can cause some Firefox difficulties. To completely uninstall and reinstall Firefox, follow these steps. Because your Firefox profile data (such as bookmarks and passwords) is saved in a different location, this method will not remove it.
• From mozilla.org, download and save the installer for the most recent official version of Firefox.
• Close Firefox (if it's open): Select Exit from the menu in Firefox.
• Make a note of where the Mozilla Firefox programme folder is located (right-click the Firefox desktop icon, select Properties from the context menu, and then click the Shortcut tab) because there may be remaining files and folders that need to be removed for a clean reinstallation.
• Firefox should be uninstalled from your machine.
• Delete the Firefox application folder, which is often located in one of the following locations:
• C:\Program Files\Mozilla Firefox
• C:\Program Files (x86)\Mozilla Firefox
• Using the software you downloaded earlier, reinstall Firefox

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