"MYPROG.exe" is your average Win32 exe who needs to be closed. "CLOSEIT.exe" is the program to do that. "CLOSEIT.exe" is uses the below code to try and terminate the application. "CLOSEIT.exe" fails. "CLOSEIT.exe" observes that "MYPROG.exe" doesn't have a window, and has no WNDCLASS (or WNDCLASSEX) registered. Code: DWORD pid = 0; HWND hWnd = FindWindow(NULL, "MYPROG.exe"); // I know it's wrong, whaddaya // think this thread is for! GetWindowThreadProcessId(hWnd, &pid); if(!TerminateProcess(OpenProcess(PROCESS_TERMINATE, false, pid), 0)) MessageBox(NULL, "Failed to close...", "Error", NULL); // code ends here "CLOSEIT.exe" needs some help.

Wait, what are you talking about?

He's asking how to go about communicating with a process that doesn't have a window. I'd answer, but I don't know off the top of my head and am too lazy to go look it up in the MSDN Library.