Reinstalling an operating system can be a frustrating and time-consuming process. Mac OS X El Capitan. Yosemite just got bigger. In order to transmit multicast flows from Dante Virtual Soundcard on OS X 10.11 (El Capitan), the IP address of the Ethernet port must be set to static, and/or the Wi-Fi port must be turned on. How to install (or reinstall) OS X. Boot from your Recovery HD partition by restarting your Mac while holding down the Command+R keys. Select Reinstall OS X, and click Continue. Click Continue to begin the process of installing or reinstalling OS X. Read the license agreement.

The new OS X El Capitan features a new Split View, features in Safari, Mail, Notes, Maps, and Photos, and more. To get your hands on all this new stuff, you have to install the operating system on your Mac.

If you want to perform a typical OS upgrade, it’s easy. You download it through the App Store. Here, we’ll go through the steps of installing EL Capitan from Yosemite.

It’s about preparation

Before you install the upgrade, there’s a little bit of prep work you should do. Our article on how to get your Mac ready for OS X 10.11 El Capitan is what you should read before you proceed. It covers:

• Compatible hardware and older versions of OS X
• Verifying the health of your Mac
• Installing updates
• Backups
• Encryption issues

Go read that article and come back here when you’re ready to go.

How to download El Capitan

Apple provides the El Capitan upgrade through its App Store. The download is a bit over 6GB, so you may want to download it at a time when you have other things to do—how long the download takes depends on your Internet connection and the amount of activity at the App Store. Or you can use your Mac while you wait, but be ready to save your work and quit when the download is done.

To download El Capitan, launch the App Store app in your Applications folder (or go to Apple menu > App Store). You’ll probably find El Capitan right away, especially if go to the App Store soon after the official release. Apple will probably have a banner at the top promoting El Capitan, but if you don’t see one, you can probably find it in the Free section in the far right column (you might have to scroll down to see it). And you can always do a search on El Capitan.

When you get to the El Capitan page in the App Store, click on the Download button. You may have to enter your Apple ID name and password, and after you do, the installer will download.

Copy the installer

When the download finishes, the installer automatically launches. Don’t click Continue in the installer just yet. What you may not know is that the installer is downloaded to your Applications folder and then deleted after the installation is done.

If you ever need the installer again, you can get it in the App Store. But I like to make a copy of the installer. I often have to perform OS installations, so I make a bootable flash drive that I can use; it’s a lot faster than waiting for the download.

To copy the installer, you need to hold down the Option key as you drag the Install OS X El Capitan app in your Applications folder to the copy destination. If you don’t hold down Option, you’ll create an alias, not a copy.

Install El Capitan

OK, now you can click that Continue button in the installer window. (If the installer isn’t running, go to your Applications folder and double click the Install OS X El Capitan app.) You’ll be asked to agree and then confirm that you agree to the license agreement.

The next screen will ask you to select the disk for the El Capitan installation. If you have one storage device with one partition, you’ll see it in the installer window. But if you have multiple storage devices and/or multiple partitions, you can select the one you want by clicking the Show All Disks button. Make your selection and click Install.

Reinstall Mac El Capitan Download

To continue, you must enter your username and password. The install will prepare to install, restart your Mac, and perform the installation. The Mac may restart again during the installation process. The install will take several minutes, so you may want to go for a walk, call your mom, take a nap, or catch up on chores while the software does its thing.

Reinstall Mac Os El Capitan

When the installation is finished, the Mac will restart and you’ll need to log in with your username and password. You may be asked if you want to send diagnostic data to Apple and that you need to log in with your Apple ID, and then a setting up screen will appear and go away. You’re done.

Want to do a clean install of El Capitan?

A clean installation is when you install the operating system on a blank storage device. You can do this by creating a bootable El Capitan installer, and then use it as the boot drive for your Mac. You run Disk Utility to erase your drive and then proceed with the El Capitan installation.

Once the installation is done, you use Migration Assistant to transfer your data from a Time Machine backup.

Reinstall Mac Os El Capitan Error

Why should you do a clean install? Maybe you partitioned your storage device and want to change the scheme. Or maybe you’ve installed and removed lots of apps over time and want to get right of any lingering software components—if this is the case, don’t restore your data from a Time Machine backup. Manually copy your files and reinstall your software.

Rachel is trying to sell her Mac, but…

My friend was wiping my Mac so I could sell it and I’m pretty sure they’ve deleted the start up disk? It’s not letting me reinstall the OS on a recovery startup.

She wonders about a fix. There are a couple of options with an erased partition.

Because Recovery didn’t work, the fastest way to install fresh is to make or borrow a macOS installer on a USB flash drive or a disk drive. We have instructions for making a bootable installer with macOS Sierra (as well as archived versions for several previous releases). You need at least an 8GB flash drive. The article includes instructions on obtaining the installer, which might involve you having to use someone’s else Mac to download it, if you don’t have a replacement Mac on hand yet.

But if you can’t get access to another Mac or the necessary drive, it’s still possible to use a different Recovery mode on all recent Macs, dating back to 2010. Normally, you can start up a Mac while holding down Command-R to boot into what Apple now calls macOS Recovery. That allows you to run Disk Utility, reinstall or wipe and install the system, access Terminal for command-line functions, and so on. In that mode, when you choose to reinstall without erasing the drive, my recollection is that Recovery looks for the current OS system installer on your startup disk in the Applications folder, and uses that. (Apple doesn’t document that, and I haven’t had to test that for years.)

Failing finding it, Recovery downloads the currently installed version of macOS (or OS X), which is about 5GB. When complete, it installs it and reboots, and places the installer in the Applications folder.

However, there’s yet another option: macOS Recovery over the Internet, which requires either a Mac model released in 2012 or later, or most 2010 and 2011 models with a firmware upgrade applied. There, the Mac reaches out over a Wi-Fi or ethernet connection to download the relatively modest Recovery software, which then bootstraps the download of the full macOS installer.

Apple says Internet-based Recovery should happen automatically on supported models, and you should see a spinning globe when that mode is invoked while the download occurs. However, if you have normal Recovery installed and it refuses to install macOS for some reason, you can manually invoke Internet Recovery.

While Command-R at startup always installs whatever the most recent version you installed on your Mac, holding down Command-Option-R brings down the very latest compatible version that can be installed. Apple also offers Shift-Command-Option-R, which installs the version of OS X or macOS with which your computer shipped, or the next oldest compatible system still available for download.

(Apple just changed this behavior with 10.12.4, but if you’re using Internet Recovery for a clean install on an erased drive, the new behavior should be active as it will be pulled from the version of Recovery that’s bootstrapped from Apple’s servers. The pre-10.12.4 option is simply Command-Option-R, but it acts like the new Shift-Command-Option-R, installing the shipped OS or the oldest compatible version.)

Apple recommends the Command-Option-R option as the only safe way to reinstall a Mac with El Capitan or earlier versions of macOS if you want to be sure your Apple ID doesn’t persist even after erasure.

Reinstall Mac Os El Capitan Without Losing Data

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El Capitan Os X Download

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