uses
CommCtrl;
procedure TForm1.DateTimePicker1DropDown(Sender: TObject);
var
wnd: HWND;
Style: Integer;
begin
wnd := DateTime_GetMonthCal(DateTimePicker1.Handle);
if wnd <> 0 then
begin
Style := GetWindowLong(wnd, GWL_STYLE);
SetWindowLong(wnd, GWL_STYLE, Style or MCS_NOTODAY or MCS_NOTODAYCIRCLE);
end;
end;
{
The calendar will still highlite the current day but the circle and the
today display at the bottom are gone.
}