I just download the .Net 3.0 SDK to start playing around with. The start-up program keep crashing when I try to run it though. It will get all the way through the selection of what should be installed and what directory to install it to. When you go to start to download the parts the setup program hangs. Turns out it has something to do with the built in Firewall. I turned off the firewall and everything worked. If you having trouble getting Setup to run, try turning off the firewall during the installation.