Imports System
Imports System.Configuration


Public Class UsingDpapiProtectedConfigurationProvider


    ' Protect the connectionStrings section.
    Private Shared Sub ProtectConfiguration()

        ' Get the application configuration file.
        Dim config As System.Configuration.Configuration = _
        ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None)

        ' Define the Dpapi provider name.
        Dim provider As String = _
            "DataProtectionConfigurationProvider"


        ' Get the section to protect.
        Dim connStrings As ConfigurationSection = _
        config.ConnectionStrings

        If Not (connStrings Is Nothing) Then
            If Not connStrings.SectionInformation.IsProtected Then
                If Not connStrings.ElementInformation.IsLocked Then
                    ' Protect the section.

                    connStrings.SectionInformation.ProtectSection(provider)


                    connStrings.SectionInformation.ForceSave = True

                    config.Save(ConfigurationSaveMode.Full)

                    Console.WriteLine( _
                    "Section {0} is now protected by {1}", _
                    connStrings.SectionInformation.Name, _
                    connStrings.SectionInformation.ProtectionProvider.Name)

                Else
                    Console.WriteLine( _
                    "Can't protect, section {0} is locked", _
                    connStrings.SectionInformation.Name)
                End If
            Else
                Console.WriteLine( _
                "Section {0} is already protected by {1}", _
                connStrings.SectionInformation.Name, _
                connStrings.SectionInformation.ProtectionProvider.Name)
            End If

        Else
            Console.WriteLine( _
            "Can't get the section {0}", _
            connStrings.SectionInformation.Name)
        End If
    End Sub 'ProtectConfiguration



    ' Unprotect the connectionStrings section.
    Private Shared Sub UnProtectConfiguration()

        ' Get the application configuration file.
        Dim config As System.Configuration.Configuration = _
        ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None)

        ' Get the section to unprotect.
        Dim connStrings As ConfigurationSection = _
        config.ConnectionStrings

        If Not (connStrings Is Nothing) Then
            If connStrings.SectionInformation.IsProtected Then
                If Not connStrings.ElementInformation.IsLocked Then
                    ' Unprotect the section.
                    connStrings.SectionInformation.UnprotectSection()

                    connStrings.SectionInformation.ForceSave = True
                    config.Save(ConfigurationSaveMode.Full)

                    Console.WriteLine( _
                    "Section {0} is now unprotected.", _
                    connStrings.SectionInformation.Name)

                Else
                    Console.WriteLine( _
                    "Can't unprotect, section {0} is locked", _
                    connStrings.SectionInformation.Name)
                End If
            Else
                Console.WriteLine( _
                "Section {0} is already unprotected.", _
                connStrings.SectionInformation.Name)
            End If

        Else
            Console.WriteLine( _
            "Can't get the section {0}", _
            connStrings.SectionInformation.Name)
        End If
    End Sub 'UnProtectConfiguration



    Public Shared Sub Main(ByVal args() As String)

        Dim selection As String = String.Empty

        If args.Length = 0 Then
            Console.WriteLine( _
            "Select protect or unprotect")
            Return
        End If

        selection = args(0).ToLower()

        Select Case selection
            Case "protect"
                ProtectConfiguration()

            Case "unprotect"
                UnProtectConfiguration()

            Case Else
                Console.WriteLine( _
                "Unknown selection")
        End Select

        Console.Read()
    End Sub 'Main

End Class 'UsingDpapiProtectedConfigurationProvider

using System;
using System.Configuration;

public class UsingDpapiProtectedConfigurationProvider
{

    // Protect the connectionStrings section.
    private static void ProtectConfiguration()
    {

        // Get the application configuration file.
        System.Configuration.Configuration config =
                ConfigurationManager.OpenExeConfiguration(
                ConfigurationUserLevel.None);

        // Define the Dpapi provider name.
        string provider = 
            "DataProtectionConfigurationProvider";


        // Get the section to protect.
        ConfigurationSection connStrings =
            config.ConnectionStrings;

        if (connStrings != null)
        {
            if (!connStrings.SectionInformation.IsProtected)
            {
                if (!connStrings.ElementInformation.IsLocked)
                {
                    // Protect the section.
                    connStrings.SectionInformation.ProtectSection(provider);

                    connStrings.SectionInformation.ForceSave = true;
                    config.Save(ConfigurationSaveMode.Full);

                    Console.WriteLine("Section {0} is now protected by {1}",
                        connStrings.SectionInformation.Name,
                        connStrings.SectionInformation.ProtectionProvider.Name);

                }
                else
                    Console.WriteLine(
                         "Can't protect, section {0} is locked",
                         connStrings.SectionInformation.Name);
            }
            else
                Console.WriteLine(
                    "Section {0} is already protected by {1}",
                    connStrings.SectionInformation.Name,
                    connStrings.SectionInformation.ProtectionProvider.Name);

        }
        else
            Console.WriteLine("Can't get the section {0}",
                connStrings.SectionInformation.Name);

    }


    // Unprotect the connectionStrings section.
    private static void UnProtectConfiguration()
    {

        // Get the application configuration file.
        System.Configuration.Configuration config =
                ConfigurationManager.OpenExeConfiguration(
                ConfigurationUserLevel.None);

        // Get the section to unprotect.
        ConfigurationSection connStrings =
            config.ConnectionStrings;

        if (connStrings != null)
        {
            if (connStrings.SectionInformation.IsProtected)
            {
                if (!connStrings.ElementInformation.IsLocked)
                {
                    // Unprotect the section.
                    connStrings.SectionInformation.UnprotectSection();

                    connStrings.SectionInformation.ForceSave = true;
                    config.Save(ConfigurationSaveMode.Full);

                    Console.WriteLine("Section {0} is now unprotected.",
                        connStrings.SectionInformation.Name);

                }
                else
                    Console.WriteLine(
                         "Can't unprotect, section {0} is locked",
                         connStrings.SectionInformation.Name);
            }
            else
                Console.WriteLine(
                    "Section {0} is already unprotected.",
                    connStrings.SectionInformation.Name);

        }
        else
            Console.WriteLine("Can't get the section {0}",
                connStrings.SectionInformation.Name);

    }


    public static void Main(string[] args)
    {

        string selection = string.Empty;

        if (args.Length == 0)
        {
            Console.WriteLine(
                "Select protect or unprotect");
            return;
        }

        selection = args[0].ToLower();

        switch (selection)
        {
            case "protect":
                ProtectConfiguration();
                break;

            case "unprotect":
                UnProtectConfiguration();
                break;

            default:
                Console.WriteLine("Unknown selection");
                break;
        }

        Console.Read();

    }


}

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <connectionStrings>
    <add name="NorthwindConnectionString" 
      connectionString="Data Source=webnetue2;Initial Catalog=Northwind;User ID=aspnet_test;Password=test"
      providerName="System.Data.SqlClient" />
  </connectionStrings>
</configuration>

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <connectionStrings>
    <EncryptedData>
      <CipherData>                <CipherValue>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</CipherValue>
      </CipherData>
    </EncryptedData>
  </connectionStrings>
  <configProtectedData defaultProvider="RsaProtectedConfigurationProvider">
    <providers>
      <clear />
      <add keyContainerName="NetFrameworkConfigurationKey" cspProviderName=""
        useMachineContainer="true" useOAEP="false" description="Uses RsaCryptoServiceProvider to encrypt and decrypt"
        name="RsaProtectedConfigurationProvider" type="System.Configuration.RsaProtectedConfigurationProvider,System.Configuration, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" />
      <add useMachineProtection="true" description="Uses CryptProtectData and CryptUnProtectData Windows APIs to encrypt and decrypt"
        keyEntropy="" name="DataProtectionConfigurationProvider" type="System.Configuration.DpapiProtectedConfigurationProvider,System.Configuration, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" />
    </providers>
  </configProtectedData>
</configuration>