on 06-25-2011 06:39 PM
You are wearing an alpha layer mask. You'll see it in your inventory if you look in the WORN tab for an item that has an icon that looks like a T-Shirt with a grid pattern on it. The mask is there to hide the incredibly ugly parts of your SL feet. Without it, you'd see something that looks like a tumor growing out of your heels when you are wearing heeled shoes. Not all alpha layer masks are created equal, however. Whoever made yours probably made it to match a particular size and shape of shoe or boot. If you're wearing smaller shoes, the mask will be hiding parts of your foot that were never supposed to be invisible. The cure is to switch that layer mask for another one that hides less of your feet. You should have received one with whatever shoes you are wearing. If not, there are LOADS of free masks in world. Try several until you get one your like.
BTW, if you are wearing "old style" shoes (pre-alpha layer), the problem is a mis-sized invisiprim --- essentially the same issue but caused by a special invisible prim instead of an alpha layer mask.