My laptop is set to go to sleep when not in use, but when I have it set to use Dual screens, after I "wake it up", all I can see is the mouse on the second screen, flickering. If I unplug the VGA cable, the laptop screen wakes up, and I can see the log-in screen. Once I plug the VGA cable back in, the second screen "wakes up" too.
This problem does not occur on startup, and I have set the second screen to be my main display - but I do often disconnect the laptop to take it with me. I have also changed the settings to make the laptop screen my main display, and the issue still occurs, just on the laptop screen instead.
This has only just started happening, around the time of the last update (2017-06 Cumulative Update for Windows 10 Version 1607 for x64-based Systems (KB4022715)).
Running Windows 10 Home, Acer Aspire E 15. Let mem know if additional information is required.