FixExec is a program that is designed to fix executable file associations for the .bat, .exe, and .com file extensions.
If the program detects any of these associations are missing, changed, or hijacked, the settings will be set back to the original Windows defaults. When file associations for batch, executable, or COM files are changed, it could cause your executables to no longer start. For example, when you double-click on a .bat, .exe, and .com file the programs will not start, and Windows will ask what you would like to start the program with. FixExec is designed to resolve these issues by rebuilding the executable file association Windows Registry keys that have become damaged.
FixExec should be used by experienced users. It did detect my Windows 10 as Windows 8, and it runs as DOS not giving you any options besides run or close.