What is wrong with my sony vaio wireless network?

have a sony vaio vgn-nr32l laptop and recently it cannot find any wireless networks after powering up. It thinks the Wireless LAN swtitch is off but it is on. The only way for it to find a network I have found is to uninstall the drivers then re-boot. Once re-installed they can find networks no problem. Any idea why this is happening? I have windows 6

SONY VAIO EE Series VPCEE42FX/WI Notebook AMD Athlon II Dual-Core P360(2.30GHz) 15.5" 4GB Memory DDR3 1066 500GB HDD

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