I just got myself a brand new Toshiba Satellite L670-187 17,3" notebook. On first boot it worked fine and I could just connect to my wireless network immediately. However, when the notebook has been turned off for several hours, my WLAN adapter suddenly is no longer detected (nor is it visible in Device Management). Only my LAN adapter is detected and operational.
When I click "Detect new hardware" in Device Management, it detects the WLAN adapter but it won't connect to any wireless networks, instead it just displays the wireless signal bars with a red X in my systray. If I reboot, the wireless network is automatically detected and connected to.
When I power of the laptop and reboot after a few hours, suddenly the WLAN adapter has gone missing again. I turned off the option that Windows is allowed to power off the device to save power, have reinstalled Windows, reinstalled all drivers and tried all available drivers for the WLAN adapter I could find. As far as I know, it works fine under Ubuntu so I figure it's a Windows issue. Furthermore, the issue persists when using a not-OEM Windows disk to reinstall.
The network switch is turned to ON and FN + F8 doesn't do anything.
Below are the specs:
CPU:
Type : Intel® Core™ i3-350M Processor
Speed : 2.26 GHz
Front Side Bus : 1.066 MHz
3rd level cache : 3 MB
Memory:
Size : 4,096 (2,048 + 2,048) MB
Max expansion : 8,192 MB
Technology : DDR3 RAM (1,066 MHz)
OS:
Genuine Windows® 7 Home Premium 64-bit (pre-installed, Toshiba-HDD recovery)
Wireless network adapter:
Realtek RTL8191SE Wireless LAN 802.11n PCI-E NIC 802.11b/g/n
Any ideas anyone?
UPDATE
If I update the driver automatically with Windows, the adapter is not detected anymore at all until I reinstall the original driver. I have already performed a BIOS update without success.