I have a Belkin N150 router. Several Windows XP machines and one Ubuntu machine connect to it successfully.
The problem: A certain Windows 7 Home Premium machine connects inconsistently. (DW 1501 Wireless-N Half-Mini network card. There is also a Broadcom Virtual Wireless adapter, driver version 18.104.22.168).
Usually, the network utility says that it was able to achieve only a partial connection. The network icon shows a connection, but nothing actually works, The troubleshooting utility says nothing.
This Windows 7 machine connects without problems to other wifi networks. This happened with WPA/WPA-2 personal security.When I removed the password from the wifi router, other machines could connect with no password. But the Windows 7 XP network utility now told me that the router had not been configured. If I tried to connect without configuring the router through the Windows 7 network utility, it again failed to connect properly. When I let Windows 7 configure the router, it assigned a random password -- and now the other machines could connect with that password, but the Windows 7 machine still achieved only a "partial" connection.