QuickBooks Issue

[Judy LG]

I just installed Windows 10 on my new HP. If I open QuickBooks and leave it open for a long time, it disappears from the task bar at the bottom of the page. If I try to open it again, it tells me that it's already open but I don't see it anywhere. Is this supposed to happen, and if so, where is it hiding? I've heard that things are "hidden" in Windows 10.