Taskbar freezes in place, hiding bottom of apps

I have my taskbar set to automatically hide itself, which is important to my workflow. HOWEVER, after a few hours of work, the taskbar reappears and freezes in place, hiding the bottom of whatever window I'm working on: the Send button for emails, the worksheet tabs for Excel, etc. (All Windows programs would normally shrink to fit the smaller window as soon as the taskbar reappears, but they continue to fill the whole screen, as if the taskbar is not there, except that the taskbar is there and hides their lowest section.)

I've found that restarting Explorer always solves the problem immediately--the taskbar disappears, and when it reappears, the apps adjust to fit--so something in this component is freezing up. Any thoughts?

It is annoying to have to restart Explorer every few hours. And I really need the space the disappearing taskbar leaves. Incidentally, I tried upgrading from Home to Pro, just in case that would help; no go.