VB.NET从active directory中删除用户

嗨,我正在尝试创建一个VB.NET应用程序,这将(希望)减少一些花费在我的部门帮助热线电话的时间。我一直坚持的部分是如何使用VB.NET从组中删除用户。下面是我一直在玩的代码:

Public Shared Sub RemoveUserFromGroup(ByVal deUser As String, ByVal GroupName As String)
    Dim entry As DirectoryEntry = ADEntry()
    Dim mySearcher As DirectorySearcher = New DirectorySearcher(entry)

    mySearcher.Filter = "(&(ObjectClass=Group)(CN=" & GroupName & "))"
    mySearcher.PropertiesToLoad.Add("OrganizationalUnit")
    mySearcher.PropertiesToLoad.Add("DistinguishedName")
    mySearcher.PropertiesToLoad.Add("sAMAccountName")

    Dim searchResults As SearchResultCollection = mySearcher.FindAll()
    If searchResults.Count > 0 Then
        Dim group As New DirectoryEntry(searchResults(0).Path)
        Dim members As Object = group.Invoke("Members", Nothing)
        For Each member As Object In CType(members, IEnumerable)
            Dim x As DirectoryEntry = New DirectoryEntry(member)
            MessageBox.Show(x.Properties("sAMAccountName").Value)
            If x.Properties("sAMAccountName").Value = deUser Then
                MessageBox.Show(searchResults.Item(0).Path.ToString)
                MessageBox.Show(x.Properties("sAMAccountName").Value)
                'group.Invoke("Remove", New Object() {x.Properties("OrganizationalUnit").Value})
                group.Properties("member").Remove(x.Properties("OrganizationalUnit").Value)
            End If

        Next
    End If

当我运行程序时,我在group.properties行收到一个COMException was unhandled,unspecified错误。使用group.invoke时,我收到错误targetInvoke异常未处理。

我是VB.NET新手,如果有人能提供帮助,我将不胜感激。

我在.NET2.0中编写代码,因为我不确定它所在的服务器是否安装了3.5。