As you can see, there’s something wrong with that leg. It was a simple model of a person based on the Noob To Pro wikibook. The first is in solid mode, and the second in texture mode. Can anyone explain this issue?
It looks like you’ve accidentally flipped some surface normals inside out. Go into edit mode, face select, select all faces, and press Ctrl N to recalculate them to the outside.
I don’t think the problem is the normals but the fact that nothing’s there. Just click all surrounding verts and hit F. The reason why i say this is because it should show in texture mode. As a matter of fact, i think that might be edit mode because the inside of faces dont show on texture mode.