Imports System.Runtime.Serialization.Formatters
...
    Public Sub LoadSomething (ByRef SomeInputBuffer as SomeType)
            Dim XMLSerializer As Soap.SoapFormatter = New Soap.SoapFormatter
            Dim XMLStream As FileStream = New FileStream("C:\somefile.xml", FileMode.Open, FileAccess.Read, FileShare.ReadWrite)
            SomeInputBuffer = CType(XMLSerializer.Deserialize(XMLStream), SomeInputType)
            XMLStream.Close()
    End Sub
    Public Sub SaveSomething (ByRef SomeOutputBuffer as SomeType)
            Dim XMLSerializer As Soap.SoapFormatter = New Soap.SoapFormatter
            Dim XMLStream As FileStream = New FileStream("C:\somefile.xml", FileMode.Create, FileAccess.Read, FileShare.Read)
            XMLSerializer.Serialize(XMLStream, SomeOutputBuffer)
            XMLStream.Close()
    End Function

' N.B. You'll need to add a reference to System.Runtime.Serialization.Formatters in your project
Option Explicit On 
Option Strict On
Imports System.Data
Imports System.IO
Imports System.Runtime.Serialization.Formatters
Module modMain

    Sub Main()
        Dim CapitalCities As Hashtable = New Hashtable
        Dim InputBuffer As Object

        With CapitalCities 'Enter some data into the hashtable
            .Add("England", "London")
            .Add("France", "Paris")
            .Add("Japan", "Tokyo")
            .Add("USA", "Washington")
            .Add("Liechtenstein", "Vaduz")
        End With

        ' Save it to disk
        SaveSomething(CType(CapitalCities, Object), Directory.GetCurrentDirectory() & "CapitalCities.xml")

        ' Clear out the object to prove it's being reloaded from disk
        CapitalCities = Nothing

        ' Load hashtable from disk
        LoadSomething(InputBuffer, Directory.GetCurrentDirectory() & "CapitalCities.xml")

        CapitalCities = CType(InputBuffer, Hashtable) ' We needed some memory to write to
        InputBuffer = Nothing

        Dim CapitalCitiesEnum As IDictionaryEnumerator = CapitalCities.GetEnumerator
        With CapitalCitiesEnum
            Do While .MoveNext
                ' List contents
                Console.WriteLine("The capital of " & CType(.Key, String) & " is " & CType(.Value, String))
            Loop
        End With

        Console.Write("Press enter...") : Console.ReadLine()
    End Sub

    Public Sub LoadSomething(ByRef SomeInputBuffer As Object, ByVal FilePath As String)
        Dim XMLSerializer As Soap.SoapFormatter = New Soap.SoapFormatter
        Dim XMLStream As FileStream = New FileStream(FilePath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite)
        Try
            SomeInputBuffer = XMLSerializer.Deserialize(XMLStream)
        Finally
            XMLStream.Close()
        End Try
    End Sub
    Public Sub SaveSomething(ByRef SomeOutputBuffer As Object, ByVal FilePath As String)
        Dim XMLSerializer As Soap.SoapFormatter = New Soap.SoapFormatter
        Dim XMLStream As FileStream = New FileStream(FilePath, FileMode.Create, FileAccess.ReadWrite, FileShare.Read)
        Try
            XMLSerializer.Serialize(XMLStream, SomeOutputBuffer)
        Finally
            XMLStream.Close()
        End Try
    End Sub
End Module