Game icons not appearing

[blackout]

the following games have somehow replaced their shortcut icons with that funny image of a piece of paper with a folded corner that you sometimes see:
blue shift,
opposing force,
half-life 2, lost coast & episode one,
portal,
nightmare house 2 (which I'm dowloading now)
source sdk base (which is also downloading now for nightmare house, I don't intend to use it nor know how to do so.)

I've had this issue for a while, and mostly ignored it, but when nightmare house appeared with no Icon I became a little concerned, so does anyone know how to fix this?

help is appreciated.

 

[tschumann]

Have you tried re-creating the shortcuts?