About Minimum and Maximum Scale

Each layer is best viewed in a certain zoom range, and outside that range, it might be pointless to display the layer. You set the zoom thresholds for each layer.

You can see your layer as long as the map zoom is between the layer's minimum and maximum zoom setting. If the zoom is smaller or larger, then the layer is invisible. Too see layers outside the current zoom, use the Map Tools toolbar buttons to zoom in and zoom out on the map.

What do you want to do?