I have installed Windows 8.1 preview. My HP ENVY dv6-7398ca Notebook PC was previously running Windows 8. There is a problem with the Ralink RT5390R 802.11bgn Wi-Fi Adapter. Upon restarting the computer the computer does not find networks, though they are there. Uninstalling the driver, rebooting the computer, then reinstalling the driver from the HP provided driver update file restablishish the network adapter.
After doing this for several days, I have not found another solution and believe the driver has not been updated for the new operating system. If anyone has had a similar problem?