Oh my, that Redmond OS called Vista is truly a freakish beast. Today my girlfriends laptop refused to connect to my new Apple Time Capsule. I had my Time Capsule configured for personal WPA/WPA2 over 802.11 b/g/n. My girlfriends Vista laptop was able to connect and authenticate, but was unable to get a DHCP lease, it ended up with one of those 169.xxx.xxx.xxx addresses. The steps to remedy the problem were really bizarre.
I reconfigured my Time Capsule to use no wireless security. I then connected her Vista laptop, it could get a DHCP lease. I re-enabled all security. Adjusted the network settings on her laptop to use WPA2. And it works flawlessly, I can even do ipconfig /renew from a command prompt.
Vista: The dumbest operating system ever if you ask me.