Have you tried a system restore? Try restoring to before you installed this icon packager program.
Another thing to try is to enter regedit (Start > run > type "regedit")
Navigate to HKEY_Local_Machine\Software\Microsoft\Windows\Current Version\Explorer\
Look for the Shell Icons
and delete this entry. You may need to log off and log back on afterwards for changes to take effect.
Let me know how you go