I installed the update to Windows 10 version 1511 at the end of November and have since been unable to wake my system after sleep. The system starts to wake after a keyboard interaction (lights on, fans, disk spinning), but the screen stays dark. After 30+ seconds the system reboots itself and I can log in, but obviously loose any application state from sleep.
After a couple of these reboot occurrences Windows offered to fix my install and one of the options was to roll back to previous build. This fixed the issue, pointing to update 1511 as the culprit. However, I know Microsoft's philosophy for Win 10 is that updates are required (OS as a service), so this is not a long term, nor maybe even short term solution.
I reinstalled the update 1511 proactively and the wake after sleep issue returned.
Has anyone discovered a fix?