Error: it contains an object field at offset 75 that is incorrectly aligned

[aannn]

Error as like this-->object field at offset 75 that is incorrectly aligned or overlapped by a non-object field. But here size constant is 3 so I think after 72 offset will be 75..If I change the offset to 76 it will works fine. I think reason is that size of int is 4. After changing that code will be like this.

[FieldOffset(72)]
            [MarshalAs(UnmanagedType.ByValArray,SizeConst= 3)]
            public int[] DC;

            [FieldOffset(76)]
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 8)]
            public float[] WIN;


            [FieldOffset(84)]
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 20)]
            public byte[] name;

            [FieldOffset(104)]
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 3)]
            public byte[] SET;

            [FieldOffset(107)]
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 50)]
            public byte[] ID;

But at that time I got the error as object field at offset 107 that is incorrectly aligned or overlapped by a non-object field..Can anyone tell me what is the main reason behind this..

Thanks..