Sometimes icons may not appear clearly due to corrupted icon cache or may be due to viruses infection and other reasons you can manually able to rebuild icon cache and correct those icons but Icon Cache Rebuilder rebuilds corrupted icon cache with a single click.
If icons not displayed correctly then you can remove iconcache.db from local file and then restart Explorer and then reboot your Computer for quick fix which rebuilds icon cache automatically.
You can use free, portable Icon Cache Rebuilder also.Run the application, click Rebuild button and wait for the Explorer to refresh, restart your Computer.New Icon cache will be build after your Computer restart.
User need to close Icon Cache Rebuilder only after Explorer refresh is completed.
Icon Cache Rebuilder is freeware, portable no installation required.