VBA: Login using Windows Authentication

authentication, ldap, ms-access, vba

Solution

If the user is already authenticated via their Windows login, why make them enter the details again?

If you need to know which user is logged in, you can get the username very easily by the following function:

Declare Function IGetUserName Lib "advapi32.dll" Alias "GetUserNameA" (ByVal sBuffer As String, lSize As Long) As Long

Function GetUserName() As String

    On Error Resume Next

    Dim sBuffer As String
    Dim lSize As Long
    Dim x As Long

    sBuffer = Space$(32)
    lSize = Len(sBuffer)
    x = IGetUserName(sBuffer, lSize)
    GetUserName = left$(sBuffer, lSize - 1)

End Function

Problem

I have a an Access App that requires the user to enter their Windows domain user and password to enter. I have used the following VBA code to accomplish this: ``` Function WindowsLogin(ByVal strUserName As String, ByVal strpassword As String, ByVal strDomain As String) As Boolean 'Authenticates user and password entered with Active Directory. On Error GoTo IncorrectPassword Dim oADsObject, oADsNamespace As Object Dim strADsPath As String strADsPath = "WinNT://" & strDomain Set oADsObject = GetObject(strADsPath) Set oADsNamespace = GetObject("WinNT:") Set oADsObject = oADsNamespace.OpenDSObject(strADsPath, strDomain & "\" & strUserName, strpassword, 0) WindowsLogin = True 'ACCESS GRANTED ExitSub: Exit Function IncorrectPassword: WindowsLogin = False 'ACCESS DENIED Resume ExitSub End Function ``` I notice that sometimes when the information is entered correctly, access is denied. I tried to debug once and it gave the error: "The network path was not found. " on the `Set oADsObject = oADsNamespace.OpenDSObject)` line. Not sure why this occurs sometimes. Is it better to convert to LDAP instead? I have tried but can't construct the LDAP URL correctly.

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