I've been in this situation a couple of times before, but I've never been able to fix it ... not until today. Let's assume that somehow your network setup in Windows gets screwed up. Ie. you've no network connection, the network adapter in Device Manager has a small yellow exclamation mark meaning it has some obscure problem that prevents it from normal functioning. And of course re-installing the adapter won't help because you get an obscure "error occurred during the installation of the device"
error message (maybe you even get a "The system cannot find the file specified."
message along too) ... or even better, you cannot uninstall the adapter at all because you get a "Failed to uninstall the device. The device may be required to boot up the computer."
error message. All seems to be lost.