I have installed Windows 8 x64 on a MacBook Air 13" purchased in August 2013.
The Windows Wired Ethernet (Using the Thunderbolt to RJ45 converter) was working fine for sometime
However, after installting some updates, the Ethernet adpator first was disabled and would not enable, even though the option existed.
On subsequent booting the adaptor disappered from the Adapter configuration under Network and Sharing
The adaptor is visible under Networking Devices in the Device Manager
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