Problems when authenticating against the Active Directory using Forms Authentication and Visual Basic .NET

[Paul East]

I have recently followed the document to allow authentication against Active Directory using Forms authentication as described in the the Microsoft Knowledge Base Article 326340 ([url]http://support.microsoft.com/default.aspx?scid=kb;EN-US;326340[/url])

I can authenticate correctly, but when I attempt to retrieve the groups for the user I get the following error

Object reference not set to an instance of an object

I have changed the code slightly to pull back the properties I have access to for the user but memberOf is not listed

Have I missed something, or is there some AD configuration needed to expose this

The code I'm working with is below

I hope someone can assist me with this

Thanks in advance

Paul Eas

Public Function GetGroups() As Strin
Dim search As DirectorySearcher = New DirectorySearcher(_path
search.Filter = "(cn=" & _filterAttribute & ")
search.PropertiesToLoad.Add("memberOf"

Dim groupNames As StringBuilder = New StringBuilde

Tr
Dim result As SearchResult = search.FindOn

'---------------> The error occours when the line below is uncommented
'Dim propertyCount As Integer = result.Properties("memberOf").Coun

'Dim dn As Strin
'Dim equalsIndex, commaInde

'Dim propertyCounter As Intege

'For propertyCounter = 0 To propertyCount -
'dn = CType(result.Properties("memberOf")(propertyCounte r), String

'equalsIndex = dn.IndexOf("=", 1
'commaIndex = dn.IndexOf(",", 1
'If (equalsIndex = -1) The
'Return Nothin
'End I

'groupNames.Append(dn.Substring((equalsIndex + 1), (commaIndex - equalsIndex) - 1)
'groupNames.Append("|"
'Nex

Catch ex As Exceptio
Throw New Exception("Error obtaining group names. " & ex.Message
End Tr

Return groupNames.ToString(
End Function

[Beginner]

Someone does not have MemberOf properties. You need to test If
result.Contains("MemberOf"), or something like that. It's a pain if you
have a long list, hope they change the behavior in the futuer to treat null
as empty string.

"Paul East" <paul.east@gmacrfc.co.uk> wrote in message
news:23DDF00C-8D75-42F9-BC92-0232E13A5C3B@microsoft.com...

> I have recently followed the document to allow authentication against

Active Directory using Forms authentication as described in the the
Microsoft Knowledge Base Article 326340
([url]http://support.microsoft.com/default.aspx?scid=kb;EN-US;326340[/url]).

>
> I can authenticate correctly, but when I attempt to retrieve the groups

for the user I get the following error:

>
> Object reference not set to an instance of an object.
>
> I have changed the code slightly to pull back the properties I have access

to for the user but memberOf is not listed.

>
> Have I missed something, or is there some AD configuration needed to

expose this?

>
> The code I'm working with is below.
>
> I hope someone can assist me with this,
>
> Thanks in advance,
>
> Paul East
>
> Public Function GetGroups() As String
> Dim search As DirectorySearcher = New DirectorySearcher(_path)
> search.Filter = "(cn=" & _filterAttribute & ")"
> search.PropertiesToLoad.Add("memberOf")
>
> Dim groupNames As StringBuilder = New StringBuilder
>
> Try
> Dim result As SearchResult = search.FindOne
>
> '---------------> The error occours when the line below is uncommented:
> 'Dim propertyCount As Integer =

result.Properties("memberOf").Count

>
> 'Dim dn As String
> 'Dim equalsIndex, commaIndex
>
> 'Dim propertyCounter As Integer
>
> 'For propertyCounter = 0 To propertyCount - 1
> 'dn =

CType(result.Properties("memberOf")(propertyCounte r), String)

>
> 'equalsIndex = dn.IndexOf("=", 1)
> 'commaIndex = dn.IndexOf(",", 1)
> 'If (equalsIndex = -1) Then
> 'Return Nothing
> 'End If
>
> 'groupNames.Append(dn.Substring((equalsIndex + 1),

(commaIndex - equalsIndex) - 1))

> 'groupNames.Append("|")
> 'Next
>
> Catch ex As Exception
> Throw New Exception("Error obtaining group names. " &

ex.Message)

> End Try
>
> Return groupNames.ToString()
> End Function

[Paul East]

Thanks Beginner

The memberOf attribute is definately not in the list of exposed attributes from the code I posted

Has anyone else tried this code against their AD

Paul.

[Beginner]

Didn't quite get what you are trying to say. You mean you didn't use
memberOf?

"Paul East" <paul.east@GMACRFC.co.uk> wrote in message
news:540950F3-C861-46CE-BFDD-C476457AA72C@microsoft.com...

> Thanks Beginner,
>
> The memberOf attribute is definately not in the list of exposed attributes

from the code I posted.

>
> Has anyone else tried this code against their AD?
>
> Paul.