40.3 Firefox does not start, but older versions will be

Firefox 40.0.3 will not start or open. I Uninstaller and put on 36.0.3 and it runs. Once I go to the About tab it will automatically download the latest version. Then, when I click on Firefox icons, that nothing is happening. I repeated this process several times with the same results.
XP Pro SP3

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Have you tried Mode safe mode of Firefox with normal computer?

In this case, one of the other programs on your system is causing the
problem. Look at the list of programs on your system. Anything weird?

Windows: Start > Control Panel > uninstall programs.
Mac: Open the folder "Applications".
Linux: See your user manual.

Tags: Firefox

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