Hide ICON of an external appication on system tray

Hi Experts!
Here code hide the clock in the system tray
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function ShowTrayClock(bValue: Boolean) : Boolean;
var
 TrayWnd, TrayNWnd, ClockWnd: HWND;
begin
 TrayWnd  := FindWindow('Shell_TrayWnd', nil);
 TrayNWnd := FindWindowEx(TrayWnd, 0, 'TrayNotifyWnd', nil);
 ClockWnd := FindWindowEx(TrayNWnd, 0, 'TrayClockWClass', nil);
 Result := IsWindow(ClockWnd);
if Result then
begin
   ShowWindow(ClockWnd, Ord(bValue));
   PostMessage(ClockWnd, WM_PAINT, 0, 0);
end;
end;
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i need hide icons of another application, for example: Internet Download Manager,...
Thanks!