1. Navigate to and open.../Applications/Utilities/Disk Utility
2. Click on "Macintosh HD" in upper left, then press "Repair Permissions" .
3. If that does not solve the problem, navigate to /System/Library and delete...
4. Navigate to /System/Library/Caches and delete the folder...
5. Restart and see if the problem still exist.
6. If that does not fix the problem, go to ~/Library/Preferences and delete..
7. Restart and see if the problem still exist.