Question

I’m working on upgrading a solution in VB.NET that is heavily based on Active Directory. As of now, I’m trying to add a PC restriction to a new AD User upon user creation. Essentially, I need to update the Logon To attribute to include 1 or more PCs, how do I go about doing this?

I learned that I am interested in the IADsUser property “LoginWorkstations” (thanks to http://msdn.microsoft.com/en-us/library/Aa746340). As of now, I have code that can fetch this attribute from any AD user, but I cannot set it.

Here is the code I have to fetch the attribute:

Dim userADObject As new DirectoryEntry(ADPath)
Dim logonToPC as String = userADObject.InvokeGet("LoginWorkstations")(0).ToString

That will fetch the first restricted PC (if there is one) and save it in logonToPC and will look something like “PC10000“

That works great, so intuitively I would assume something like this would work:

Dim userADObject As new DirectoryEntry(ADPath)
Dim args() As Object = {"PC100001"}
userADObject.InvokeSet("LoginWorkstations", args)

But it doesn’t work… It just throws a rather unhelpful exception.

I’ve tried testing this approach with a different attribute and it works just fine. Not much out there on Google either unfortunately…

Any help would be greatly appreciated.

Answer 1

Found the solution that works. I took marc_s’s code and modified a bit to work properly. here’s what I have:

Dim userADObject As New DirectoryEntry(Me.ADPath)
'Grab the previous restriction, because we may have to clear it first in the future
Dim priorRestriction As String = userADObject.Properties("userWorkstations").Value

If priorRestriction = "" Then
     'Simply add
     userADObject.Properties("userWorkstations").Add("PC001,PC002")
Else
     'Important - We have to clear the old restriction before adding the new
     userADObject.Properties("userWorkstations").Remove(priorRestriction)
     'Now add the new restriction
     userADObject.Properties("userWorkstations").Add(priorRestriction & ",PC003")
End If
'Commit!
userADObject.CommitChanges()

Something that gave me some pretty good grief what that I you can’t have a space in the string being added. Example: .Add("PC001, PC002") has to be .Add("PC001,PC002")