What causes the Windows 7 Photo Viewer menu bar to steal the arrow key focus?

Question

As I am hitting the left or right arrow keys to cycle through images using Windows Photo Viewer, the menu bar will inevitably end up stealing the focus from the viewer controls at the bottom. When it does this, pressing the arrow keys does nothing until I hit tab enough times to bring the focus back to the image navigation panel.

Why does it do this? What am I doing wrong?

Please do not recommend alternatives image viewers. That does not solve the actual problem with this particular program.

Answer 1

If you're on a laptop, this might be the result of accidentally brushing the trackpad, as trackpads often have a tap-to-click function (I am aware that there's often a guard against this sort of thing, but it's not always perfect). It could also be another key near the arrow keys doing it. For example, some computers (if not all, not 100% sure) have a key right next to arrow keys that, when pressed, opens a menu in some applications. If you're bumping this key (or it's just oversensitive), this could be the cause of losing focus.