Yesterday while opening Firefox in my system I happened to face a problem that “Firefox is already running, but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system.”
I didn’t take much attention about the error as I have faced so many times while working. Normally it can be fixed by Refreshing few times, or by logging off the system or by Restarting the system.
However, unfortunately I was not able to solve the error by above methods. Even more, I have spent about an hour in searching the solution in the net. But, I couldn’t get the exact solution. Besides, I have tried my best ideas but still it was not solved.

Want to create Fake Error Messages ?

Finally, I caught the idea. I just went to the registry by typing “Regedit” in Run command. After entering Registry, I went to Edit and chose Find, then I got the find dialog box (You can make the find the Dialog box by pressing Ctrl + F). In the command, I just typed firefox.exe and pressed enter. When the file was detected, I deleted it completely. I tried this few times until the file was completely deleted. Then I refreshed my system few times and it started to work properly.
But, you can try this out in other way. Login using Administrator account, go to “C:\Documents and Settings\Administrator\Application Data\Mozilla”, and delete the file Mozilla in the navigated folder. If you will not get the solution means, you can delete the Mozilla folder by navigating “C:\Documents and Settings\Administrator\Application Data” this address. After you deleting this, you will be prompted to import the settings of Internet explorer or some other browsers. If you want to have this setting means choose Import otherwise choose “Do not import” option. Then the Firfox will start working, now you can add your addons or you can import the Backup of Firefox which has been taken earlier times.

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