Dim key As Microsoft.Win32.RegistryKey = _
  Microsoft.Win32.Registry.CurrentUser.OpenSubKey( _
  "Software\Microsoft\Windows\CurrentVersion\Run", True)
   If AutostartEnable = True Then
      'SubKey erzeugen
   Else
      key.DeleteValue(My.Application.Info.AssemblyName, False)
   End If
   key.Close()

Public Function DeleteSubKeyValue(ByVal MainKey As RegistryKey, ByVal sKey As _
  String, ByVal sKeyName As String) As Boolean
        Dim rkKey As RegistryKey
        Try
            'open the given subkey
            rkKey = MainKey.OpenSubKey(sKey, True)
            'check to make sure the subkey exists
            If Not rkKey Is Nothing Then 'subkey exists
                'delete the subkey
                MainKey.DeleteValue(sKeyName, True)
                Return True
            Else  'subkey doesnt exist
                'throw an exception
                Throw New Exception("The SubKey provided doesnt exist! Please" & _
                  "check your entry and try again")
                Return False
            End If
        Catch ex As Exception
            MessageBox.Show(ex.Message, "Error: Deleting SubKey Value", _
              MessageBoxButtons.OK, MessageBoxIcon.Error)
            Return False
        End Try
    End Function

DeleteSubKeyValue(Registry.CurrentUser, _
  "Software\Microsoft\Windows\CurrentVersion\Run", _
  My.Application.Info.AssemblyName)