Attached Link: http://www.morphography.uk.vu/dlprop.html

This usually happens when you're using the Poser ground, since it isn't actually situated at Y=0 but slightly below it (and it seems to have unique trouble with shadows even if you drop your characters down to it). If you're using a prop, I can only suggest that you check that your character really is standing on it. The prop I use (link to my downloads) has edges on it, so you can easily use the orthogonal cameras (front, back, left, right) to adjust your character's feet to be on the ground. The other thing to do which improves shadows is to select a spotlight's shadow camera. This has to be done from the menu below the document window, and will give you a weird view, but if you zoom in carefully so that its field of view covers only the parts of your scene that will be shadowed, it will improve the efficiency of the shadow map rendering.