Also, for me to be able to keep the Essentials Dashboard (which is only a feature of Windows Server 2012 R2 Essentials) I have to first install Windows Server 2012 R2 Essentials, then upgrade to Windows Server 2012 R2 Standard. However because it is a headless system (does not have a screen), it was virtually impossible to simply upgrade it. The WD Sentinel (DX 4000) Storage Appliance from Western Digital comes with stock Windows Storage Server 2008, I wanted to upgrade it to Windows Server 2012 R2 Standard to make use of the following features: However, PLEASE BACKUP ALL YOUR DATA FIRST. This image will keep your D drive intact, it only formats C drive.I will give it a shot for a couple of weeks. My DX4000 is upgraded to 4GB of RAM, yet still it is far too slow to be functional for me. Just like Windows Server 2012 R2, Windows Server 2016 is too slow to run on this device.NIC Drivers are also now fully compatible. Instructions are the same, except you can create your USB using USB Image Tool which is far simpler this time. Update!!! I have created a new image for Windows Server 2016 Standard on WDSentinel DX4000.