Build 15002 - 2nd Monitor - Taskbar - Start Button - Blue Screen
Lenovo T420 with 2nd Monitor and Keyboard added for Desktop Work. I installed the new preview version 15002. After completing boot, none of my taskbar programs were on the taskbar. On the taskbar were the Start button, Cortana, Task View, Date and Time only. However, clicking on any of them was useless. They did not respond. So I had no access to any of my programs unless they were on the desktop.
One of the programs I did have on my desktop was a portable version of Tweaking.coms's Windows Repair version 3.9.22. I ran it and my machine Blue Screened, "System Service Exception".
I disconnected the 2nd monitor and did a hard reboot. This time everything came up fine. the taskbar was populated properly and worked properly. I attached the 2nd monitor (VGA). It worked and the taskbar remained populated and working. I was able to get to Settings, the Control Panel, and to the Device Manager. All drivers were reported as properly working in the DM. Tweaking.com Windows Repair was again attempted and Blue Screened.
I booted again with 2nd monitor attached. Same problem. I rebooted with 2nd monitor not attached. Everything seemed to work fine except Windows Repair again Blue Screened.
I am considering going back to the previous preview version but will not do so if I can get these problems fixed