Did apple server have some maintenance?
Open your Terminal and put this command
sudo mkdir -p /Users/Shared sudo chown root:wheel /Users/Shared sudo chmod -R 1777 /Users/Shared
sudo mkdir -p /Users/Shared
sudo chown root:wheel /Users/Shared
sudo chmod -R 1777 /Users/Shared
解决OX10.11.4 不能授权的问题
原文：http://www.cnblogs.com/xiguapijiamuguanaicha/p/5424965.html
