Do you have the Firefox icon on your quick launch? Right click on it, and select Open New Window. Sometimes this works. If it opens, close it by Menu > File > Exit.

This is not a cure but will make it easier if Firefox locks up in Windows. https://support.mozilla.org/questions/997866 {web link}

If you still have issues, let us know.

Sorry it took so long to answer. I tried what you suggested and it still does not work.

You may have a corrupt xulstore.json file. https://support.mozilla.org/en-US/kb/changes-toolbars-and-window-sizes-are-not-saved

I tried the refresh Firefox and nothing happens. Is there a problem with Firefox and Windows 10?

Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) to see if that helps.

• http://www.bleepingcomputer.com/tutorials/how-to-start-windows-in-safe-mode/
• http://www.7tutorials.com/4-ways-boot-safe-mode-windows-10

How do you boot in safe mode..

Jimd6121 said

How do you boot in safe mode..

The instructions are in the links cor-el posted.

• Windows: Turn on, or reboot the computer. During the boot-up, press the <F8> key. This will bring up the boot menu.