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i have unstalled firefox because it stoped working now there are folder for firefox i cant delete because firefox is running even tho i have uninstalled it ??

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fire fox stopped working on my windows 8.1 laptop. every time I tried to open it, it gave an error message saying Firefox can not as an instance of Firefox is already running even though there wasn't. so I tried uninstall reinstall and no change. so now have uninstalled again but there are still files and folder for Firefox on my pc, and i can not delete these files because it is already running? even though i have uninstalled?

fire fox stopped working on my windows 8.1 laptop. every time I tried to open it, it gave an error message saying Firefox can not as an instance of Firefox is already running even though there wasn't. so I tried uninstall reinstall and no change. so now have uninstalled again but there are still files and folder for Firefox on my pc, and i can not delete these files because it is already running? even though i have uninstalled?

Chosen solution

Download Firefox For All languages And Systems {web link} Save the file. Then;

Start your Computer in safe mode.

Starting The Computer In Safe Mode;
Free Online Encyclopedia


Using your file browser, open the Programs Folder on your computer.

Windows: C:\Program Files C:\Program Files (x86) Mac: Open the "Applications" folder. Linux: Check your user manual.


Look for, and rename any Mozilla or Firefox folders by adding .old to them.

After rebooting the computer, run a registry scanner. Then run the installer. If all goes well, remove the OLD folders when you are done.

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Chosen Solution

Download Firefox For All languages And Systems {web link} Save the file. Then;

Start your Computer in safe mode.

Starting The Computer In Safe Mode;
Free Online Encyclopedia


Using your file browser, open the Programs Folder on your computer.

Windows: C:\Program Files C:\Program Files (x86) Mac: Open the "Applications" folder. Linux: Check your user manual.


Look for, and rename any Mozilla or Firefox folders by adding .old to them.

After rebooting the computer, run a registry scanner. Then run the installer. If all goes well, remove the OLD folders when you are done.