Cannot connect to Server as Administrator with Impersonate - vb.net

Question

I have to impersonate as administrator to view some network folders, but it doesn't work beacause the application recognizes the current logged account. This is the class that i used that I found on the internet :
Public Class Impersonator
Private _username As String
Private _password As String
Private _domainname As String
Private _tokenHandle As New IntPtr(0)
Private _dupeTokenHandle As New IntPtr(0)
Private _impersonatedUser As System.Security.Principal.WindowsImpersonationContext
Public Sub New(ByVal username As String, _
ByVal password As String)
Dim nameparts() As String = username.Split(Convert.ToChar("\"))
If nameparts.Length > 1 Then
_domainname = nameparts(0)
_username = nameparts(1)
Else
_username = username
End If
_password = password
End Sub
Public Sub New(ByVal username As String, _
ByVal password As String, _
ByVal domainname As String)
_username = username
_password = password
_domainname = domainname
End Sub
Public ReadOnly Property username() As String
Get
Return _username
End Get
End Property
Public ReadOnly Property domainname() As String
Get
Return _domainname
End Get
End Property
Public ReadOnly Property currentWindowsUsername() As String
Get
Return System.Security.Principal.WindowsIdentity.GetCurrent().Name
End Get
End Property
Public Sub BeginImpersonation()
'Const LOGON32_PROVIDER_DEFAULT As Integer = 0
'Const LOGON32_LOGON_INTERACTIVE As Integer = 2
Const LOGON32_LOGON_NEW_CREDENTIALS As Integer = 9
Const LOGON32_PROVIDER_WINNT50 As Integer = 3
Const SecurityImpersonation As Integer = 2
Dim win32ErrorNumber As Integer
_tokenHandle = IntPtr.Zero
_dupeTokenHandle = IntPtr.Zero
If Not LogonUser(_username, _domainname, _password, LOGON32_LOGON_NEW_CREDENTIALS, LOGON32_PROVIDER_WINNT50, _tokenHandle) Then
win32ErrorNumber = System.Runtime.InteropServices.Marshal.GetLastWin32Error()
Throw New ImpersonationException(win32ErrorNumber, GetErrorMessage(win32ErrorNumber), _username, _domainname)
End If
If Not DuplicateToken(_tokenHandle, SecurityImpersonation, _dupeTokenHandle) Then
win32ErrorNumber = System.Runtime.InteropServices.Marshal.GetLastWin32Error()
CloseHandle(_tokenHandle)
Throw New ImpersonationException(win32ErrorNumber, "Unable to duplicate token!", _username, _domainname)
End If
Dim newId As New System.Security.Principal.WindowsIdentity(_dupeTokenHandle)
_impersonatedUser = newId.Impersonate()
End Sub
Public Sub EndImpersonation()
If Not _impersonatedUser Is Nothing Then
_impersonatedUser.Undo()
_impersonatedUser = Nothing
If Not System.IntPtr.op_Equality(_tokenHandle, IntPtr.Zero) Then
CloseHandle(_tokenHandle)
End If
If Not System.IntPtr.op_Equality(_dupeTokenHandle, IntPtr.Zero) Then
CloseHandle(_dupeTokenHandle)
End If
End If
End Sub
Public Class ImpersonationException
Inherits System.Exception
Public ReadOnly win32ErrorNumber As Integer
Public Sub New(ByVal win32ErrorNumber As Integer, ByVal msg As String, ByVal username As String, ByVal domainname As String)
MyBase.New(String.Format("Impersonation of {1}\{0} failed! [{2}] {3}", username, domainname, win32ErrorNumber, msg))
Me.win32ErrorNumber = win32ErrorNumber
End Sub
End Class
Private Declare Auto Function LogonUser Lib "advapi32.dll" (ByVal lpszUsername As [String], _
ByVal lpszDomain As [String], ByVal lpszPassword As [String], _
ByVal dwLogonType As Integer, ByVal dwLogonProvider As Integer, _
ByRef phToken As IntPtr) As Boolean
Private Declare Auto Function DuplicateToken Lib "advapi32.dll" (ByVal ExistingTokenHandle As IntPtr, _
ByVal SECURITY_IMPERSONATION_LEVEL As Integer, _
ByRef DuplicateTokenHandle As IntPtr) As Boolean
Private Declare Auto Function CloseHandle Lib "kernel32.dll" (ByVal handle As IntPtr) As Boolean
<System.Runtime.InteropServices.DllImport("kernel32.dll")> _
Private Shared Function FormatMessage(ByVal dwFlags As Integer, ByRef lpSource As IntPtr, _
ByVal dwMessageId As Integer, ByVal dwLanguageId As Integer, ByRef lpBuffer As [String], _
ByVal nSize As Integer, ByRef Arguments As IntPtr) As Integer
End Function
Private Function GetErrorMessage(ByVal errorCode As Integer) As String
Dim FORMAT_MESSAGE_ALLOCATE_BUFFER As Integer = &H100
Dim FORMAT_MESSAGE_IGNORE_INSERTS As Integer = &H200
Dim FORMAT_MESSAGE_FROM_SYSTEM As Integer = &H1000
Dim messageSize As Integer = 255
Dim lpMsgBuf As String = ""
Dim dwFlags As Integer = FORMAT_MESSAGE_ALLOCATE_BUFFER Or FORMAT_MESSAGE_FROM_SYSTEM Or FORMAT_MESSAGE_IGNORE_INSERTS
Dim ptrlpSource As IntPtr = IntPtr.Zero
Dim prtArguments As IntPtr = IntPtr.Zero
Dim retVal As Integer = FormatMessage(dwFlags, ptrlpSource, errorCode, 0, lpMsgBuf, messageSize, prtArguments)
If 0 = retVal Then
Throw New System.Exception("Failed to format message for error code " + errorCode.ToString() + ". ")
End If
Return lpMsgBuf
End Function
End Class
End Class

Answer 1

Did you actually try to acces the network resource or did you only determine it was not working with the: WindowsIdentity.GetCurrent.Name result ?
The way it works:
Interactive login with default provider works only properly if the user can actually connect to the server. In older Windows version, this was not enforced and could be used instead of the ones below.
Logon_New_Credential (with Winnt50 provider) will impersonate the user for remote connections but will use the original user locally
Logon_Network (with Winnt50 provier) will impersonate you as the desired user locally but the token will fails if you try to initiate a connection remotely.
Therefore, Logon_New_Credential will return your original user if you try WindowsIdentity.GetCurrent.Name in your impersonation loop but will use the impersonated user when accessing the network resource.
See below

Answer 2

Thank you so much Sage Pourpre , it work if i use the first option :
LOGON32_PROVIDER_DEFAULT | LOGON32_LOGON_INTERACTIVE
Currently i use this type of login, but i will documet because i would like understand the differences.