Resolving The: 'AsEnumerable' is not a member of 'System.Data.DataTable' Runtime Error

If you begin writing some LINQ to DataSet queries, and try to find the .AsEnumerable function exposed on a DataTable, you will see the following design time error occur:

'AsEnumerable' is not a member of 'System.Data.DataTable'

This is because this functionality exists in the System.Data.DataSetExtensions namespace. Add a reference to this .dll and the error will resolve, and this functionality will become available.