Hi, we have run updates on some applications. After updates, non of the machines are able to mount any external hard drives nor any dmg, iso, rar etc files. However when we activate root we are able to mount the hdd's and dmg etc files. We initially thought it might be permissions, we ran a permission test, didn't resolve the issue. We replaced the kext files ran an OS update, reset the pram and still no luck. We tried mounting it from both finder, disk utility and terminal. We are running 10.8.4 on slim iMacs. Any suggestions would be appreciated!