Whilst helping a friend to set up a home wireless network yesterday, I encountered a very unusual issue with the configuration of the wireless adapter on their laptop. The laptop was a Fujitsu Siemens Amilo L7320 and it was running Windows XP Home and contained an Atheros AR5005G WiFi adapter.
No matter what I tried, Windows simply refused to find any wireless networks. It kept saying that either the adapter is disconnected or the switch is off. The adapter was showing up fine in the Device Manager and there was no sign of a switch on the exterior of the laptop.
In the end, it turns out that you have to press Fn + F2 to enable the WiFi adapter on this model. Apparently, you also have to do this after each reboot, which Fujitsu Siemens claim to be a feature.
You learn something new every day!