My environment: Windows 7, VSTS 2010 and SQL Server 2008.
When I try to use ADO.NET to connect to SQL Server 2008, "DataSet myDataSet = new DataSet();" causes the following error.
The type 'System.Xml.Serialization.IXmlSerializable' is defined in an assembly that is not referenced. You must add a reference to assembly 'System.Xml, Version=18.104.22.168, Culture=neutral, PublicKeyToken=b77a5c561934e089'.
I have "using System.Xml ;" in my source code, but it doesn't work at all.
After adding reference of System.xml (v4.0.30319), it works.