If you're trying to run an executable by only specifying its name, Windows looks for the file in the following locations:
- The current working directory.
Windows directory only (no subdirectories are searched).
- Directories listed in the PATH environment variable.
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths (also
HKEY_CURRENT_USER since Windows 7)
Microsoft actually recommends "registering" applications in the
App Paths subkey to avoid the need for applications to modify the system
PATH environment variable. The application's installer will register the executable.