@BigRedConsulting, Maximize is available, but my goal is not to maximize.  QB is not in "One Window" mode.  At one point I did invoke that mode just to observe the behavior, but I would never choose to actually use it that way.  Minimize is also available, even though QB is not in One Window mode, and it does in fact minimize the window. The "Move" option is also available, which is how I managed to move the window up far enough to see the bottom edge (using Windows accessibility features).  But FYI, the bottom of the window is the same as the top and the sides, in that the edge cannot be "grabbed" to resize it.

Yes, I am indeed in Multiple Windows mode.

Yes, the same thing happens with other company files.

Yes, the same thing now happens on another computer, although, when the behavior first manifested itself on my main computer, it was still working as expected on my "server" machine.  It wasn't until days or weeks later that the server machine became afflicted.

I'm using Release R14P.