private FancyTreeNode OrganisationalUnitToFancyTreeNode(ADOrganisationalUnit OrganisationalUnit)
        {
            FancyTreeNode[] children = OrganisationalUnit.Children == null
                ? null
                : OrganisationalUnit.Children.Select(ou => OrganisationalUnitToFancyTreeNode(ou)).ToArray();

            return new FancyTreeNode()
            {
                key = OrganisationalUnit.DistinguishedName,
                title = OrganisationalUnit.Name,
                folder = true,
                tooltip = OrganisationalUnit.DistinguishedName,
                children = children,
                unselectable = false
            };
        }