Missing icons on macOS Sierra

I had to run the below commands to make my icons come back. It took a while to find, but it finally sorted everything.

sudo find /private/var/folders/ -name com.apple.iconservices -exec rm -rf {} \;
sudo rm -rf /Library/Caches/com.apple.iconservices.store
killall Dock

This happened to me after upgrading to High Sierra - Having tried all of the icon cache suggestions without any success I booted in to "safe mode" and the problem was fixed.

1. Restart Mac holding the shift key as soon as you hear the startup chime and hold until the boot sequence shows the Apple
2. Log in and check the icons
3. Restart to get out of safe mode (where many things are disabled)

4. Log in normally and verify the icon database is rebuilt correctly under a normal mode start up

   • https://support.apple.com/en-us/HT201262 Using Safe Mode to isolate issues