Vielleicht hilft das weiter...
Delphi-Quellcode:
procedure PopUpMyWindow;
var
Window: THandle;
begin
Window := FindWindow(NIL, 'myAppXYZ');
if Window <> 0 then
begin
ShowWindow(Window,SW_SHOWNORMAL);
BringWindowToTop(Window);
end
end;
procedure OnTimer(Sender: TObject);
begin
if ... then
PopUpMyWindow;
end;