My wireless LAN adapter is not connecting to any of my near wireless routers. I opened up Device manager, and checked under "Network Adapters"; and it was just not showing up. (I can see my Ethernet LAN adapter though). This configuration was working fine just before I went to sleep last night and I have verified that other devices can see the wireless router.
Here are some things that were tried in the course of trying to reactivate wireless:
Toggling the wireless switch on the left side of the laptop
Toggling Fn-F5 to check for the wireless radio indicator
Checked BIOS (pressing F1) Config -> Network -> Wireless LAN and Wimax Radio set to "On"
Disabling and enabling the Ethernet LAN and Bluetooth adapters
Scaning for hardware changes
Reinstallation of drivers
I even tried System restore
Ultimately, the issue was resolved by a complete shutdown and then cold boot rather than just selecting Shutdown/Restart. Seems like some bit just got stuck and power cycling was required to resolve it.