blackandwhitebg

Hi everyone, I understand this topic is little old, but I just saw it and would like to submit a solution. The mistake comes from here: hwndButton = FindWindowEx(hwndDialog, IntPtr.Zero, "Button", "2"); In the calc version of WINDOWS 7 is different. These are more than 1 control with class "#32770", which is the problem. This code selects the first one, and this is wrong, as the buttons are in the second. A possible solution would be: IntPtr hwnd = (IntPtr)FindWindow(null, "Calculator"); IntPtr hwndFrame = FindWindowEx((IntPtr)hwnd, IntPtr.Zero, "CalcFrame", string.Empty); IntPtr hwndDialog = FindWindowEx(hwndFrame, IntPtr.Zero, "#32770", string.Empty); IntPtr hwndDialog2 = FindWindowEx(hwndFrame, hwndDialog, "#32770", string.Empty); IntPtr hwndButton = FindWindowEx(hwndDialog2, IntPtr.Zero, "Button", "5"); Cheers, B&W