How to log into AD while off the domain in Excel - excel

Question

So I have been trying to add a level of security to a tool, and I came upon this post. The code works when on the network/domain, but I need to use this somehow for people who are remote and not on the network, nor vpn'ed into the network. Is this possible? I am learning as I go here, so this may not even be feasible in the first place. Just looking for every avenue possible.
Example Code:
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
EDIT: So #user2140261 told me about trying the LogonUser function from Advapi32.dll which looks like below:
Private Declare Function LogonUser Lib "advapi32.dll" Alias "LogonUserA" (ByVal lpszUsername As String, ByVal lpszDomain As String, ByVal lpszPassword As String, ByVal dwLogonType As UInteger, ByVal dwLogonProvider As UInteger, ByRef phToken As IntPtr) As Boolean
Sub LoginTest()
Dim logname As String
Dim logpass As String
Dim domainstring As String
logname = "username"
logpass = "password"
domainstring = "domain.com"
Call WindowsLogin(logname, logpass, domainstring)
End Sub
For some reason, this crashes Excel all together. Any reason why?

Answer 1

Not sure what the sub WindowsLogin is dong in your orininal code but try the below:
Private Declare Function LogonUser Lib "Advapi32" Alias "LogonUserA" _
(ByVal lpszUsername As String, ByVal lpszDomain As String, ByVal lpszPassword As String, _
ByVal dwLogonType As Long, ByVal dwLogonProvider As Long, phToken As Long) As Long
Public Sub LogUserOn()
Dim strUserName As String
Dim strPassword As String
Dim strDomain As String
Dim bResult As Boolean
strUserName = "UserName"
strPassword = "Password"
strDomain = "Domain"
bResult = LogonUser(strUserName, strDomain, strPassword, 2, 0, 0)
If bResult Then
MsgBox "Successfully Logged User In"
Else: MsgBox "And Error Occured While Trying To Log User In " & vbCrLf _
& "Error Code:" & Err.LastDllError
End If
End Sub

Answer 2

As the answer in the post you referenced said, if you just need to know who is using the app, and apply security based on that, then you can just get the logged-in user's name from the OS. The user can log into their laptop when disconnected using their cached credentials, and your app will be able to lock down whatever is needed based on the identity asserted by the OS.
Update
There are a couple of ways to get the User's identity from the OS. One is the environment variables %USERDOMAIN% and %USERNAME%. Another is the WScript.Network object:
Set WshNetwork = WScript.CreateObject("WScript.Network")
WScript.Echo "Domain = " & WshNetwork.UserDomain
WScript.Echo "User Name = " & WshNetwork.UserName
You can validate that the user is logged into the correct domain, and then provide access to the secured features.