Hello,
In addition, try to manually update your driver, you will need to select the .inf file (the working atheros driver). Here's the link to download your Atheros driver.
Drivers for Atheros AR9485WB and Windows 7
An update will be appreciated.
In case someone has not find a solution about this problem, I want to report that after a lot of research for another vaio laptop with the same problem, I found that if you install the VAIO smart network utility, then the wifi will work again.
I had installed the atheros driver and the card was seems ok, but it was not discovering any networks, but after I installed this utility, magically it started working.
Install everything that it's related with network from the sony utilities and drivers and you will be fine.
I hope this helps.
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