Can someone please help me, I have this xml snippet
123
XSD.EXE is the tool that produces classes specifically for the purpose of XML Serialization. If it produces partial classes, that's because they work for XML Serialization. That's not what your problem is.
Try using XSD.EXE and serializing / deserializing. If you get an exception again, then please catch it and then post the results of ex.ToString().