Process copia = new Process();
copia.StartInfo.Arguments = "copy TresenRaya.exe C:\\";
copia.StartInfo.FileName = "CMD.EXE";
copia.Start();

Process copia = new Process();
copia.StartInfo.Arguments = "[b]/C [/b]copy TresenRaya.exe C:\\";
copia.StartInfo.FileName = "CMD.EXE";
copia.Start();

proceso.StartInfo.Arguments = "/C ...";