I test the XmlWrite/XmlRead from MemoryStrem, my codes is:
\
  DataSet ds = Will.DM.ExecuteDataset("Select * from Customer);
  MemoryStream msOri = new MemoryStream();
  ds.WriteXml(msOri);

  DataSet ds2 = new DataSet();
  ds2.ReadXml(msOri);

It compiled ok, but when it run fail at the last line:  ds.WriteXml(msOri);
Ther error message is
System.Xml.XmlException: Root element is missing.

Why?

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