Fix This device is not working properly because Windows cannot load the drivers required for this device. (Code 31) Network Adapter issue.

I'm running Windows Server 2008 R2 x64 and I have a driver that isn't signed so the Device Manager displays the following message: "Windows cannot verify the digital signature for the drivers ...

These aren't like your chipset or graphics drivers where you can (and should) update them yourself, but fortunately, Windows has a built-in scan tool to help fix file system and Windows driver errors.