Using Window NT Authentication

I am trying to retrieve a Windows NT user's password to use it for verifying a SQL Server login.  I have the code that accesses the API, but it is not executing the callback function that actullay retrievs the info.

Here is th code....


'***********************************************
'* Function to Get The UserName From Windows NT (in my form)
'***********************************************

Private Declare Function GetUserName Lib "advapi32.dll" Alias "GetUserNameA" (ByVal lpBuffer As String, nSize As Long) As Long

'******************
'* Code in my form
'*****************

'Get the Password from Windows NT
                    Dim i As Integer
                    Dim s As String
                    Dim l As Long
                    Dim b As Byte
   
                    b = &HFF
                    i = 0
                    l = 0
                    s = ""
                   
                    '?????????????why does this not execute the callback function?????????????
                    Call WNetEnumCachedPasswords(s, i, b, AddressOf callback, l)
                    txtPassword.Text = goConnect.NTPassword
 
                    'connect to SQL Server
                    If SQLTestConnection Then
                        MsgBox "Test Connection to SQL Server Successful", vbInformation, Me.Caption
     
                        'display the table list frame
                        Call FormToggle
                        fraSQLServer.Visible = False
         
                        'load the grid with table names (if not already)
                        If lstTables.ListCount = 0 Then
                            For intIndex = 0 To goConnect.TableCount - 1
                                lstTables.AddItem (goConnect.TableNames(intIndex, 0))
                            Next intIndex
                        End If
                    End If


'*************************
'* Code From a BAS Module
'*************************

'******************************
'* Gets the User's NT Password
'******************************

'undocumented function in mpr.dll
Declare Function WNetEnumCachedPasswords Lib "mpr.dll" (ByVal s As String, ByVal i As Integer, ByVal b As Byte, ByVal proc As Long, ByVal l As Long) As Long


'purpose:   to parse the .PWL file of the currently logged on user
'platform:  win '95 (ms networking, password caching enabled)
'language:  vb 5.0 sp2
'author:    todd harmon <tharmon@gyver.com>
'date:      9/16/1998
'comments:  the mpr.dll has many functions that are poorly documented,
'           this is my attemped at unraveling one of those functions
'           for visual basic programmers
'
'this sample program is provided "as is"!
'use at your own risk!

'comments/questions are welcome, see e-mail address above


'this structure is returned by the call to WNetEnumCachedPasswords
Type PASSWORD_CACHE_ENTRY
   
    cbEntry As Integer              'size of this returned structure in bytes
    cbResource As Integer           'size of the resource string, in bytes
    cbPassword As Integer           'size of the password string, in bytes
    iEntry As Byte                  'entry position in PWL file
    nType As Byte                   'type of entry
    abResource(1 To 1024) As Byte   'buffer to hold resource string, followed by password string
                                    'should this be bigger?

End Type



Public Function callback(x As PASSWORD_CACHE_ENTRY, ByVal lSomething As Long) As Integer
'callback routine for WNetEnumCachedPasswords results
Dim i As Integer
Dim s As String

    s = "Type: " & x.nType
    '1 = domains?
    '4 = mail/mapi clients?
    '6 = RAS entries?
    '19 = iexplorer entries?
   
    s = s & "     Rsrc: "
    For i = 1 To x.cbResource
        If x.abResource(i) <> 0 Then 'nulls don't display nicely
            s = s & Chr(x.abResource(i))
        Else
            s = s & " "
        End If
    Next i
   
    s = s & "     Pwd: "
   
    For i = x.cbResource + 1 To (x.cbResource + x.cbPassword)
        If x.abResource(i) <> 0 Then 'nulls don't display nicely
            s = s & Chr(x.abResource(i))
        Else
            s = s & " "
        End If
    Next i
   
    goConnect.NTPassword = s
   
    callback = True
End Function