Odd icon problem solved (mostly)

Regarding the odd icon problem, covered here last week, we have at least a partial solution: the icons come from 9Tuner. There is still a bit of mystery as to why these icons suddenly installed themselves after rebuilding the desktop and why turning ATM on and off affected their appearance, but the fundamental mystery is solved. We subsequently received a confirming reply from Craig Hockenberry (of the IconFactory). It sheds further light on the matter: As you've discovered, the culprit seems to be 9Tuner. It works by modifying the icons in the Platinum appearance directly (they are stored as 'icns' resources in the System Resources file.) When you start with extensions off, the icons probably disappear because the Appearance Manager isn't loaded and the system falls back on the icon resources in the System file. You can tell if this is happening by looking at the shadows on the folders: if they are smooth they are 32-bit and from the Appearance theme if not, they are 8-bit and from the System file. In theory, you should be able to replace the System Resources file in the System Folder to eliminate the problem (by restoring the Platinum appearance icons). Update: Jerry Du (the creator of 9Tuner) adds: "9Tuner does modify icons of type 'icns' in the System Resources file, however the described icon problem may still happen if the user modifies the icons manually without using 9Tuner (using ResEdit, for example). So far, I still don't know why turning ATM off helps resolve the problem (9Tuner does not rely on any system extensions to run)."