I recently formated my laptop, using the recovery disc and was thereafter unable to use my WLAN. In the Device Manager, the Network Adapter said no driver was installed and the network card was an unknown manufacturer. The Ethernet card's driver was installed and it is a Realtek. The system is a Gateway model number T-6345u, running Windows Vista Home Premium.
I searched Gateway's support for driver's and tried a few network driver files.
The driver/file that worked was:
M-153_WIRELESS_MARVELL_22.214.171.124_32BIT.zip - Marvell Wireless Driver