[C++] Errore "Unresolved external symbol"

[keratox]

In ambiente Visual C++ 6.0

#include <windows.h>

int APIENTRY WinMain(HINSTANCE hIstance, HINSTANCE h2Istance, char * str, int num){

	MessageBox(0, "Ciao mondo", "Keratox", 0);

	return 0;
}

Ovviamente compila bene... ma quando lo eseguo..

Linking...
LIBCD.lib(crt0.obj) : error LNK2001: unresolved external symbol _main
Debug/program.exe : fatal error LNK1120: 1 unresolved externals
Error executing link.exe.

program.exe - 2 error(s), 0 warning(s)

che devo fare?

ciao