Working in CS6 (on an old Mac), and I can't work out if what's going on here is a bug, or I've messed up. Had a white outer glow applied to some text, have screenshotted the parametres below. Got asked to make the image larger, and when I increased it from 300 px/inch to 300 px/cm, the outer glow suddenly got a black border outside of it. Tried removing the layer style and re-applying it after enlarging, and the same thing happens. Any explanation of what's happened here, and of how to get rid of it? Have added before and after pics.