I get those very annoying temp files when rendering with shadows - quit doing that and now don't get that problem. It happens with p4/ppp/p5 for me on an xp using shadowlites from some of the lighting packages that I have bought. However, when just using lights and no shadowlites - havent found any temp files. It is irratating as you are correct - harddisk management doesn't stop the problem - you must manually delete them. Perhaps what cl has done is to try to reuse these temp files they created rather than ignoring or writing over them?