El Capitan ships with a new OS X feature: System Integrity Protection (SIP), also known as “rootless” mode. This reduces the attack surface for malware that relies on modifying system files by preventing any user, whether with system administrator (“root”) privileges or not from modifying a number of operating system directories and files.
This new feature may affect the installation of some applications. In order to modify SIP, use the following instructions:
- Restart your Mac.
- Before OS X starts up, hold down Command-R and keep it held down until you see an Apple icon and a progress bar. Release. This boots you into Recovery.
- From the Utilities menu, select Terminal.
- At the prompt type exactly the following and then press Return:
- Terminal should display a message that SIP was disabled.
- From the menu, select Restart.