Windows 7 has a file which stores the icon cache, so whenever you change any icons in Windows, it might not take effect immediately. If you find that icons are not displaying correctly, or that your icon cache is corrupted, you can try rebuilding your icon cache. Rebuild Icon Cache is a simple freeware application. This application deletes the IconCache.db and Restarts the Explorer.
The tool has three options, one to rebuild the icon cache, another one to restore the original icon cache file and third option to delete the back up file of icon cache. When you rebuild the cache, it takes a back up of existing IconCache.db.
You must Start it in Administration Mode to work properly. This application is tested to work on Windows 7 32/64bit.