I'm probably a bit late to the party, but I recently set up a solution for the computer/phone repair shop I work for that does network installs of Windows so we can ditch our clunky multiple flash drive setup. I use a customized Windows PE with an OS selection script. Then, it mounts the appropriate network share for that installation and provides an Autounattend.xml so that we can skip all the questions with the exception of username and password. Usually, when somebody is using an Autounattend.xml, it's for automated deployments for an organization using KMS. In my scenario, since I work on mostly OEM computers for end users I had a major sticking point when attempting to deploy this solution using a Windows 8.1 ISO as provided by Microsoft. With Windows 10, I was able to use the generic install keys and get Windows to activate on OEM machines with no issues. This, however, doesn't seem to work with Windows 8.1. If a key is provided via the Autounattend.xml it simply won't attempt OEM activation. But, Setup.exe complains if no key is specified in the Autounattend.xml file and won't install. After banging my head against the wall repeatedly and trying the installation many times on a very slow Windows 8 OEM machine, I managed to both provide an Autounattend.xml and get Windows to do OEM activation: provide the <Key> section, but leave it blank. This way Setup.exe doesn't complain about not being able to find the key section and it leaves the automatic OEM activation process intact. Just in case this is helpful for anybody else that might find themselves in the same situation.