My Dell laptop regularly looses the windows taskbar when I disconnect and reconnect to my dual monitors.  This is very frustrating because the only solution I know of is to restart my PC.  I came across this article http://www.makeuseof.com/tag/5-steps-fix-windows-10-taskbar-issues/ which has an easy solution.

Now when I have the issue all I do is start task manager with CTRL+SHIFT+ESC and restart the windows explorer process and the taskbar reappears.