I have the same problem as you and after searching for a day for a definitive solution, i have found this one that works on another forum located here: http://www.sevenforums.com/tutorials/49819-icon-cache-rebuild.html
The reason seems to be that icons stored have for some reason disappeared (inexplicably?). The solution is also stupidly simple after i've tried every suggestion in this thread.
- go to start menu and search for: cmd
- right click on cmd and choose "run as administrator" (--> this causes command line to change from C:\users<account name> to change to: C:\windows\system32).
- turn off everything you are doing after saving your work because now you will be closing explorer.exe
- in the command line enter each command separately and with enter following each line
- taskkill /IM explorer.exe /F
- CD /d %userprofile%\AppData\Local
- DEL IconCache.db /a
- shutdown /r
- after the restart, everything should be back to normal.
This is a complete fix for the problem and not a work around and I can verify that it worked for me. Good luck all. Theres no need to grab a copy of the folder off of another computer
also, this is a repost of my post on another thread. hope it works for you.