When i open my browser it says Windows cannot find 'C:\Program Files (x86)\Mozilla Firefox\firefox.exe'. Make sure you typed the name correctly, and then try again.
ANd if you go to my computer and go to the C:\Program Files (x86)\Mozilla Firefox\ folder is the firefox.exe file there ? If not check in the Program Files Folder instead of the Program Files (x86) folder. and if it is there change the shortcut path accordingly (or uninstall\reinstall Firefox as mentioned above.)