Marking the 12th major release in Apple’s annual OS release cycle, version 10.11 El Capitan is an extension of the previous version of OS X, Yosemite, in that it focuses on adding stability, performance, and security enhancements to the already rock-solid UNIX foundation.

To help IT support staff, systems administrators, and enterprise users get up to speed on OS X El Capitan, the most important details and related resources have been compiled into this guide, which we will update as new information becomes available.

SEE: Free ebook: Executive’s guide to Apple in the enterprise

Executive summary

  • What it is: OS X El Capitan is a major release of Apple’s OS X operating systems for Mac computers and servers.
  • Why it matters: OS X El Capitan includes many enhancements to stability and performance, and increases security with new features aimed at both enterprise and consumer users. It also adds expanded support for mobile devices and collaboration using OS X Server.
  • Who this affects: Keeping in line with Apple’s upgrade policy, OS X El Capitan is free for all users running at least OS X 10.6.8 (Snow Leopard). OS X Server 5.0, the server management software that enables server configuration, is free for users of Server 4.0; all other users must purchase Server 5.0 from the Mac App Store for $19.99.
  • When it was released: Apple released OS X El Capitan on September 30, 2015 on the Mac App Store after initiating a public beta release to users that signed up for the Apple Beta Software Program on July 9, 2015.
  • How to get OS X El Capitan: All users running OS X 10.6.8 or later are eligible for a free upgrade to OS X El Capitan through the Mac App Store. Users may also opt to create a USB install drive with which to install El Capitan on multiple Macs.
  • Updates: Apple will issue periodic updates to OS X El Capitan through the Mac App Store.

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What it is

During Apple CEO Tim Cook’s keynote speech at the 2015 World Wide Developers Conference (WWDC), he removed the shroud off of Apple’s latest iteration of OS X, titled El Capitan, the successor to OS X Yosemite.

While Apple is known for its strict adherence to secrecy, particularly when it comes to hardware and software releases, the first of several betas was released to developers on June 8, 2015 at the end of the first day of WWDC 2015. A month later, Apple launched a rare public beta program, giving users the opportunity to test-drive non-optimized code and provide valuable feedback regarding bugs and software incompatibilities.

In addition to further unifying the design between its desktop (OS X) and mobile (iOS) OSes, OS X El Capitan boasts notable new features; most of the features are designed to improve OS X’s reliability and efficiency, especially when compared to OS X Yosemite. New features include:

  • Split View: Split View offers a side-by-side view of two supported apps, allowing users to jump back and forth with undivided attention.
  • Spotlight: Searches are more versatile, encompassing just about any manner of retrievable data, such as movie times, sports scores, and weather, in addition to web-based media searches or location-based data.
  • Notes: Notes received a major upgrade; this feature now includes handwriting support for written notes using a track pad or iOS device. Also, attachments are now possible for media-rich content, maps, or other files, such as PDFs with a simple drag and drop. Checklists may also be created from existing or shared data.
  • Safari: In addition to being updated, Safari now supports AirPlay per-site. This allows you to stream web content directly from your browser window instead of sharing the entire desktop.
  • Metal: This is the core graphics technology that provides access to the graphics and CPU to work together to boost performance while reducing energy consumption.
  • Performance: OS X El Capitan boasts a multitude of under-the-hood changes that serve to make your Mac work more efficiently. For instance, it’s smoother to launch apps and switch between apps, and it’s faster to render web pages and PDF documents.
  • Security: Apple included System Integrity Protection (SIP) as a way to reduce the chance for malware to infect and subsequently run, effectively mitigating threats.
  • Mail: Adding support for gestures similar to its iOS counterpart, Mail has increased ease of use through suggestions. It also detects calendar dates or contact information and offers a one-click solution to add those items to native Calendar and Contacts apps found in OS X.

OS X El Capitan comes in only one flavor. The optional OS X Server is an add-on app that enables server functionality over the base OS X Yosemite or El Capitan installation.

Some features are supported only on certain Mac hardware models or on newer models. For a full breakdown of the features and their respective requirements, check Apple’s knowledge base.

Apple’s technical specifications for OS X El Capitan

  • Minimum OS: OS X 10.6.8 Snow Leopard
  • RAM: 2 GB
  • Hard disk space available: 8.8 GB
  • Apple ID required for certain features.
  • Internet service required for certain features.

Apple’s Mac hardware requirements for OS X El Capitan

  • MacBook (Early 2015)
  • MacBook (Late 2008 Aluminum or Early 2009 or newer)
  • MacBook Pro (Mid/Late 2007 or newer)
  • MacBook Air (Late 2008 or newer)
  • Mac Mini (Early 2009 or newer)
  • iMac (Mid 2007 or newer)
  • Mac Pro (Early 2008 or newer)
  • Xserve (Early 2009)

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Why it matters

Though many OSes rebrand or redesign with each new release, Apple has a different philosophy about its flagship OS. With its 12th release of OS X, Apple has opted to move away from whiz-bang features or a complete overhaul in favor of strengthening its underlying UNIX underpinnings and core system services, while peppering in new features and security updates.

The design aesthetic is similar to previous versions of OS X; however, Apple continues toward a more platform-unified design by further integrating shared features with iOS without fully merging them. According to Apple CEO Tim Cook, it’s long been Apple’s policy that unifying the two operating systems would “subtract from both,” and the user wouldn’t “get the best experience from either.”

El Capitan works in conjunction with iOS, while still very much retaining the look and feel of OS X that users worldwide have enjoyed for well over a decade.

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Who this affects

OS X El Capitan is available to all Mac users running OS X 10.6.8 or newer as a free download.

Upgrading to OS X El Capitan is a straightforward process for devices that meet the technical requirements. Unlike competing OSes, Apple does not market multiple SKUs of its operating system.

All features come pre-loaded with each installation of OS X El Capitan, which makes licensing OS X for an entire fleet of devices as simple as it is for just one computer. No missing or disabled features and easy-to-manage licensing, coupled with the ability to natively run Windows via Boot Camp, make using Mac computers in the enterprise a worthwhile proposition, especially when considering both upfront costs (hardware) as well as back-end costs (licensing client software).

Regardless of the underlying version of OS X, the base system may be upgraded directly to El Capitan by running the Installer app downloaded. Performing a clean install is also possible, yet not necessary to make the jump to El Capitan. If you wish to perform a clean install, remember to back up your data prior to installing the new OS.

Additional resources:

SEE: iOS 9: The smart person’s guide

When this is happening

OS X El Capitan (build 10.11) was released to the public on September 30, 2015.

Build 10.11.1 was released on October 21, 2015 for download, deprecating the previous build. Available as a separate combo update as well, 10.11.1 fixes several issues, including reliability updates and stability enhancements for known bugs.

Additional resources:

How to get OS X El Capitan

OS X users running at least OS X Snow Leopard (build 10.6.8 or newer) are able to download the Install OS X El Capitan app exclusively from the Mac App Store. The installer, which tips the scales at just over 6 GB, may be used to directly upgrade an existing OS X installation to retain any existing data and applications. Once installation has completed, the installer file is safe to delete or copy if you’re upgrading multiple computers (Figure A).

Figure A

For users of OS X versions prior to build 10.6.8, there are two upgrade options: clean install and upgrade-upgrade.

Clean install

For OS X users of build 10.5 or older, the recommended solution for getting OS X El Capitan is the clean install. This process requires the creation of a USB Installer Drive for OS X El Capitan and a full backup of your existing data prior to installation.

Due to the nature of clean installs, the hard drive will be erased completely, so it’s very important to have your data backed up before proceeding. Once the install media and data backup are verified, boot the Mac with the install media and follow the prompts to format the hard drive and install a fresh copy of OS X El Capitan.

Once the process is completed and the system reboots a final time, OS X El Capitan will be installed and ready for use. Simply reconnect your backup drive, restore your data, and download your applications to restore your system to full working order.


While not a technical term per se, upgrade-upgrade refers to the process of installing a previous OS X — OS X Snow Leopard (build 10.6.8) in this case — and then upgrading to OS X El Capitan. This requires you to have access to OS X Snow Leopard’s Installation DVD Media to perform an in-place upgrade to OS X Snow Leopard; then, you can access the Mac App Store to download and perform a second in-place upgrade to OS X El Capitan.

This is time-consuming and not a recommended best practice, though it is a viable option for those wishing to retain data and applications without formatting their hard drive.

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The 10.11.1 update released on October 21, 2015 contains a number of improvements to reliability in applications, including VoiceOver and Installer.

One major fix was restoring Microsoft Office 2016 support compatibility, which was effectively broken during the 10.11 initial release period.

Fixes were included for a bug in Apple Mail that prevented some email communications from displaying in mailboxes and affected outgoing server information.

Lastly, 150 Unicode characters (emoji) were added.


The 10.11.2 update released on December 7, 2015 includes patches for over 50 security vulnerabilities.

By far, the most lauded improvements are in Wi-Fi and Handoff reliability. Some users have noted degraded performance of wireless networks after upgrading to El Capitan from a previous version of OS X, and this update resolves this issue.

Bluetooth and AirDrop received reliability improvements as well, since there were reports of devices losing connectivity or dropping off due to Bluetooth-related issues, which AirDrop requires in order to establish a connection with other devices.

Enterprise-related issues were also addressed in this update — in particular, NTLM authentication for Safari users and a Configuration Profile bug, which caused edited profiles to be removed altogether instead of updated.

Additional resources:


The 10.11.3 update was released on January 19, 2016. Clocking in at about the same size as version 10.11.2, this update mainly includes bug fixes and security patches for vulnerabilities that could allow attackers to obtain privilege escalation to compromise a Mac.

One fix is aimed squarely at enterprise administrators that implement .pkg files to deploy software. This update will retain .pkg file receipts in the /var/db/receipts directory when performing an in-place upgrade from OS X Yosemite.

Also included is an important fix that corrects a bug preventing users with 4K monitors from waking their computers from sleep mode.

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The 10.11.4 security-focused update was released on March 21, 2016. It includes several user and enterprise features, and it improves the stability and compatibility of your Mac. This is Apple’s fix to a years-old security bug that could allow an attacker to compromise a computer to run arbitrary code at the kernel level.

Included with the more than 40 Common Vulnerability and Exposures (CVE) fixes, the update adds the ability to passcode-protect information stored in the Notes app, as well as the ability to import Evernote files and sort notes. Corrections have been made to the Photos app and its handling of RAW files and Apple’s Live Photos, which is also now supported for sharing via AirDrop and Messages.

An important feature for iBooks users is being able to store books in iCloud. Until this update, PDFs were not stored nor synced via iCloud; now PDF storage is enabled as of 10.11.4, as are a few other corrections to using VIP mailboxes with Gmail accounts in Mail, using Twitter’s URL-shortening service in Safari, and improved compatibility with Apple’s USB-C Multiport Adapters.

Enterprise users will see more server- and networking-focused content with this update, such as fixes to correct vulnerabilities in screen sharing and Migration Assistant. Also, Mail not displaying information of certain calendar events hosted on Microsoft Exchange servers. Lastly, improved compatibility and reliability of Personal Hotspot and Cisco VPN clients.

Additional resources:


The 10.11.5 update was released on May 16, 2016, bringing with it mostly stability updates. This patch includes over 65 CVE fixes for a variety of hardware-, software-, and kernel-related security vulnerabilities.

Additionally, the 10.11.5 update addresses minor glitches experienced by some users after updating to 10.11.4, causing their equipment to freeze sporadically. Enterprise customers also receive minor updates to the NetBoot and Profile Manager services when deploying more than one boot image on the network or configuration profiles that reference particular lines that would trigger unexpected hardware responses.

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The 10.11.6 update was released on July 18, 2016, and it addresses mostly stability and security issues. The update mitigates 61 CVE fixes for security-related vulnerabilities that can impact privilege escalation by means of arbitrary code execution.

This update resolves some compatibility-related issues experienced by users, preventing certain network devices from accessing SMB shares or allowing accounts managed with parental controls from retaining any saved data.

In addition, some enterprise-level compatibility concerns were improved upon or resolved outright when booting client devices from a NetBoot server or using NetBoot images. Also resolved was an issue that would cause a time out to occur when performing Active Directory authentication.

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10.11.6 Security Update 2016-002

The Security Update 2016-002 was released on October 24, 2016 as part of the 10.11.6 Combo Update released in July 2016. The integration of Security Update 2016-002 addresses important security vulnerabilities that allows malicious actors unauthorized access to Mac systems. The update mitigates 20 CVE fixes for security-related vulnerabilities that can impact privilege escalation by means of arbitrary code execution, kernel privileges, or memory corruption.

The security update is a highly recommended update, suggested by Apple for all Mac computers running OS X 10.10 (Yosemite), 10.11 (El Capitan), and 10.12 (Sierra).

Additional resources:

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