The problem started when my LAN connection stopped working: only one green light on Ethernet controller was lighting, network was beeing identified for a long time, then it became Unknown network.
To resolve this, I tried deleting network adapters in Device manager and restarting PC. These devices were re-installed (they are present in device manager), however, both LAN and Wi-Fi are not working now. Network Connections folder is empty, there is no Wi-Fi icon in tray anymore, only Airplane mode. There are two Base System Devices and Unknown Device which haven't their drivers installed. Network Services are on. Network Setting Reset did not help, either.
My network adapters are: Intel Centrino Wireless-N 2230 Qualcomm Atheros AR8161 PCI-E Gigabit Ethernet Controller (NDIS 6.30)