This won't come as a surprise for those of you who've read many of my blog entries or who've discussed security with me directly but I have a somewhat obtuse Wireless Protected Access (WPA) passphrase and I've just mistyped it on my newly built Windows Vista client machine - I want to share with you the slightly bizare outcome. I blogged about the same problem with Windows XP SP2 (in fact all versions of XP) several months ago - you can read more by clicking here.
Upon first connecting a machine to a WPA protected wireless network you are prompted to enter the Network Key (passphrase) after which the interface suggests that you're connected. That may be true at a high level but it's certainly NOT true when it comes to establishing a USEFUL connection! Inspection via "cmd> ipconfig" reveals that my system has not obtained a valid DHCP lease and hence can't communicate to other systems via TCP/IP.
To correct the problem simply disconnect, reconnect and this time enter the correct Network Key!
The bottom line is that there's no error reporting or confirmation that your WPA secret is correct - it's just misleading that's all.
I'll feed this back to the product group.