We use a lot of VB6 Components in our Internet Filtering product, IM Lock. It's just better for RAD development in a lot of cases. Plus a lot of consumers out there still have older PC's that don't support the .Net framework. The other issue is download size. Some people just don't want to download the huge (comparitively, at least) amount of data to install .NET apps. That being said, .Net does a whole lot more, and we leverage that with web services. Web Filtering Guy

We incorporate a treeview like this in our Internet Filtering product. What we have done in this case is to use a third party ActiveX control. So you might want to consider searching the web for third party controls, and testing them out for your purpose. It's easier than trying to code it all yourself. Web Filtering Guy