Welcome, Gokhan.
At a quick look, it seems your Atheros AR9271 USB wireless dongle (yours is TP-LINK branded) does not have W8 drivers available (yours are dated 7/28/2010 - W7 drivers):
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Your best solution would be to buy a new adapter that has W8 drivers
There are what looks like later W7 drivers (dated June '11), you
may get better luck with those if you don't have the finances to buy a new adapter immediately:
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