diff --git a/windows/syscall_windows.go b/windows/syscall_windows.go
index 3834459..d249919 100644
--- a/windows/syscall_windows.go
+++ b/windows/syscall_windows.go
@@ -18,6 +18,7 @@
 )
 
 type Handle uintptr
+type HWND uintptr
 
 const (
 	InvalidHandle = ^Handle(0)
@@ -213,9 +214,11 @@
 //sys	CancelIoEx(s Handle, o *Overlapped) (err error)
 //sys	CreateProcess(appName *uint16, commandLine *uint16, procSecurity *SecurityAttributes, threadSecurity *SecurityAttributes, inheritHandles bool, creationFlags uint32, env *uint16, currentDir *uint16, startupInfo *StartupInfo, outProcInfo *ProcessInformation) (err error) = CreateProcessW
 //sys	OpenProcess(desiredAccess uint32, inheritHandle bool, processId uint32) (handle Handle, err error)
-//sys	GetWindowThreadProcessId(wnd uintptr, pid *uint32) (tid uint32) = user32.GetWindowThreadProcessId
-//sys	GetShellWindow() (desktopWindow uintptr) = user32.GetShellWindow
 //sys	ShellExecute(hwnd Handle, verb *uint16, file *uint16, args *uint16, cwd *uint16, showCmd int32) (err error) [failretval<=32] = shell32.ShellExecuteW
+//sys	GetWindowThreadProcessId(hwnd HWND, pid *uint32) (tid uint32) = user32.GetWindowThreadProcessId
+//sys	GetShellWindow() (shellWindow HWND) = user32.GetShellWindow
+//sys	MessageBox(hwnd HWND, text *uint16, caption *uint16, boxtype uint32) (ret int32, err error) [failretval==0] = user32.MessageBoxW
+//sys	ExitWindowsEx(flags uint32, reason uint32) (err error) = user32.ExitWindowsEx
 //sys	shGetKnownFolderPath(id *KNOWNFOLDERID, flags uint32, token Token, path **uint16) (ret error) = shell32.SHGetKnownFolderPath
 //sys	TerminateProcess(handle Handle, exitcode uint32) (err error)
 //sys	GetExitCodeProcess(handle Handle, exitcode *uint32) (err error)
@@ -346,8 +349,6 @@
 //sys	QueryDosDevice(deviceName *uint16, targetPath *uint16, max uint32) (n uint32, err error) [failretval==0] = QueryDosDeviceW
 //sys	SetVolumeLabel(rootPathName *uint16, volumeName *uint16) (err error) = SetVolumeLabelW
 //sys	SetVolumeMountPoint(volumeMountPoint *uint16, volumeName *uint16) (err error) = SetVolumeMountPointW
-//sys	MessageBox(hwnd Handle, text *uint16, caption *uint16, boxtype uint32) (ret int32, err error) [failretval==0] = user32.MessageBoxW
-//sys	ExitWindowsEx(flags uint32, reason uint32) (err error) = user32.ExitWindowsEx
 //sys	InitiateSystemShutdownEx(machineName *uint16, message *uint16, timeout uint32, forceAppsClosed bool, rebootAfterShutdown bool, reason uint32) (err error) = advapi32.InitiateSystemShutdownExW
 //sys	SetProcessShutdownParameters(level uint32, flags uint32) (err error) = kernel32.SetProcessShutdownParameters
 //sys	GetProcessShutdownParameters(level *uint32, flags *uint32) (err error) = kernel32.GetProcessShutdownParameters
diff --git a/windows/zsyscall_windows.go b/windows/zsyscall_windows.go
index 0627373..cd5e852 100644
--- a/windows/zsyscall_windows.go
+++ b/windows/zsyscall_windows.go
@@ -2898,19 +2898,19 @@
 	return
 }
 
-func GetShellWindow() (desktopWindow uintptr) {
+func GetShellWindow() (shellWindow HWND) {
 	r0, _, _ := syscall.Syscall(procGetShellWindow.Addr(), 0, 0, 0, 0)
-	desktopWindow = uintptr(r0)
+	shellWindow = HWND(r0)
 	return
 }
 
-func GetWindowThreadProcessId(wnd uintptr, pid *uint32) (tid uint32) {
-	r0, _, _ := syscall.Syscall(procGetWindowThreadProcessId.Addr(), 2, uintptr(wnd), uintptr(unsafe.Pointer(pid)), 0)
+func GetWindowThreadProcessId(hwnd HWND, pid *uint32) (tid uint32) {
+	r0, _, _ := syscall.Syscall(procGetWindowThreadProcessId.Addr(), 2, uintptr(hwnd), uintptr(unsafe.Pointer(pid)), 0)
 	tid = uint32(r0)
 	return
 }
 
-func MessageBox(hwnd Handle, text *uint16, caption *uint16, boxtype uint32) (ret int32, err error) {
+func MessageBox(hwnd HWND, text *uint16, caption *uint16, boxtype uint32) (ret int32, err error) {
 	r0, _, e1 := syscall.Syscall6(procMessageBoxW.Addr(), 4, uintptr(hwnd), uintptr(unsafe.Pointer(text)), uintptr(unsafe.Pointer(caption)), uintptr(boxtype), 0, 0)
 	ret = int32(r0)
 	if ret == 0 {