Unfortunately, I haven't yet had the opportunity to upgrade to 7, I'm actually asking the question for a friend of mine. Currently her internet goes through a NAT gateway for the whole building. Each apartment is allowed only a single DHCP private IP. Is there a way to setup a second layer of NAT on her desktop, so internet can be shared wireless with her laptop? Desktop is running windows 7, laptop (netbook) is running XP.

Just take a router with wi-fi or an AP with dhcp server and plug her single connection into the WAN port. Whatever the IP range is they are pushing out ..say it is 192.168.1.x and her WAN IP is 192.168.1.101 In her router set the LAN IP range to be anything but 192.168.1.x something like 192.168.10.x well do In her router set her DNS to the IP of her router. This is all ASSUMING she does not need to provide any login or captive portal info to get on line now.

Unfortunately, she does need to log in. That, combined with her not owning a router, is why I am asking how I can use a window 7 box to accomplish the routing. Sorry I did not specify this ahead of time.

Hi, Get a lan network card, Make sure it is compatible with W7. Shut down the computer and unplug power cable from back. Install the card into the W7 computer. Restart computer. Then when W7 has added the lan card driver. Type in search bar ncpa.cpl hit enter. Right click the lan connection that is on the building share - properties - share this internet connection. Now with lan cable connect the second card to the routers wan connection. You should now be able to share access to the internet with other computers. Please bear in mind, that my answer is based on the details given in your post. The more I get the better the answer, Slan go foill, Paul