TransparentBlt

Can someone tell me where did i do wrong with TransparentBlt, i always get an error no matter how i change it.

Code:

void Bitmap(HDC hDC, HINSTANCE hInst, HWND hwnd)
{

	BITMAP bm;
	HDC MemDCExercising;
	HBITMAP bmpExercising;
	bmpExercising = LoadBitmap(hInst, MAKEINTRESOURCE(IDB_BITMAP3));
	MemDCExercising = CreateCompatibleDC(hDC);
	SelectObject(MemDCExercising, bmpExercising);
	if ( !TransparentBlt(hDC,0,0,bm.bmWidth, bm.bmHeight, MemDCExercising, 0, 0, bm.bmWidth, bm.bmHeight, RGB(0,0,0)))
		MessageBox(hwnd, "ERROR","ERROR", MB_OKCANCEL);
	DeleteDC(MemDCExercising);
	DeleteObject(bmpExercising);
}

the picture im using is a smiley face in a black background

Try to use HWND as argument of function and then take HDC from HWND...

you are forgetting to call GetObject() before calling TransparentBlit().
Include

Code:

GetObject(bmpExercising,sizeof(BITMAP),&bm);

before calling TransparentBlit() and everything will work fine.