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Most users traditionally switch to a new version of OS X by simply clicking the “update” button in the App Store. Undoubtedly, this is the easiest method, but at the same time it is not always the most effective, since over time many Mac users notice that their system is no longer as fast as it was at the beginning of operation, and updating does not solve the problem.

Users who constantly change and reinstall software on their Mac are especially susceptible to this problem. The reason for the decrease in performance is precisely various system garbage and “residues” from deleted programs that safely remain in place during the update. That is why many people prefer to install a “clean system”.

Things to remember before installing from scratch

First of all, be sure to back up your system. To do this, the standard set of OS X programs includes a wonderful Time Machine utility.

Also be sure to make sure that all your contacts, calendars, mail, etc. synced with iCloud (settings>iCloud)

Clean installation of OS X El Capitan step by step

2. Reboot the Mac while holding down the key option(aka alt).

3. Select a USB flash drive as boot media.

4. After the Mac boots Recovery from the USB flash drive, visually it will happen like this:

open Disk Utility and format the Mac hard drive.

5. To do this, select the hard drive partition in the panel on the left, then in the top panel click erase(do not change the format and name) then click again erase(at the bottom).

6. After formatting is complete, close Disk Utility and select reinstall OS X.

7. In the next window, select only the formatted hard drive and after completing the installation process you will receive a crystal clear OS X El Capitan.

By the way, you can reinstall the system from scratch without bothering with a flash drive. True, you need to have Capitan installed on your Mac before, also from scratch, otherwise the version of the system that came “in the box” will be installed.

So, if such a need arises, then restart your Mac while holding cmd+R, open Disk Utility and format the hard drive as shown above. Then you also choose Reinstall OS X and wait for the installation to complete.

Restoring or reinstalling software

Mac OS X software

If there is a problem with your Mac software or hardware
problem, you can use recovery utilities in Mac OS X,
to avoid problems and even restore original factory settings
software. These utilities are available in Mac OS X Utilities.
even if your computer does not boot properly.

The best thing is that if you plan to save files on your external hard drive, don't transfer them to your computer unless they have a real use. In the case of applications, it is recommended to re-download and, if they are programs with costs, you should restore your purchases so that you do not have to pay for the software again.

Once you have saved your information and are sure you want to restore the system, you will have to restart your computer. These settings can be renamed depending on the language in which you have configured your system. What you need to do is select the internal hard drive.

Mac OS X Utilities lets you do the following:

restore your computer disk using Disk Utility;

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There is a problem - there is a solution

restore software and data from Time backup
Machine;

Clean installation of OS X El Capitan step by step

Select the drive and select “Delete” in the right window. The process time will depend on the amount of information that needs to be eliminated. The process here will take a few more minutes, but once it's completed you'll have a completely clean environment. The above guide works for those who want to clean and format your computer.

Back up everything

Here's how to do it step by step in 7 steps. A full installation of this type is equivalent to "formatting" or formatting the hard drive, which will erase everything. So the first step should be. All data must be copied. Therefore it's best. Manually copy all documents, videos, files, downloads, music, etc. to an external drive. from the group employees folder, including what may be on the desktop and in other places. When you give the "Download" button the message.

restore Mac OS X Lion and Apple programs;

restore your computer to factory settings by erasing its disk and reinstalling
Mac OS X Lion and Apple programs.

If a problem is detected with your computer, it automatically opens
Mac OS X Utilities panel. You can also open it manually by rebooting
computer.

To open the Mac OS X Utilities panel, do the following:

Why and how to reinstall the operating system on a MacBook

System 3 is already installed on this computer. Depending on the connection speed, it may take from half an hour to several hours. This is done by searching for the drive connected to your desktop, clicking on the name below and changing it to "Install".

It is important that the drive name, as already stated, is set or otherwise will not work. This process does not indicate its evolution on the screen and can take up to 30 minutes, so you need to be patient and even go for a walk.

  • A terminal window will open.
  • Copy and paste the following command.
  • A terminal window will prompt you to enter your computer's administrator password.
  • At the end, check “Copy full” and “Done”.
The boot menu will appear.

Restart your computer while holding down the (x) and R keys.

Some utilities in the Mac OS X Utilities panel require
Internet access and App Store for Mac. You may need to make sure that
The computer is connected to the Internet via Ethernet or Wi-Fi.

Connect via Wi-Fi network

Select a network from the Wi-Fi status menu in the top right corner of the screen.

At this point, it is very important to complete the data backup because it will start a process that will erase everything after a restart. From there, you can run a full uninstall and format your computer's hard drive. Removal may take several minutes.

What is the best way to install the system?

The rest of the process is automatic and can take more than half an hour. If so, the files and settings are inherited, but if you want to start from scratch, it's better to say no. There are several cases where, thanks to this process, the computer has regained its original speed, stability and response speed, or at least very similar, since it must also be taken into account that the software increasingly requires and the hardware, if it has not been updated, the same.

If necessary, enter a password to access the network.

To connect to a closed network, select Connect to Another Network.
Enter your network name and password.

Recovering a disk using Disk Utility

If there is a problem with your computer or when loading
computer You see the Mac OS X Utilities panel, you may need to
restore computer disk.

Running from the macOS recovery partition

From there, it will download the first piece of software to begin booting the system.

  • The first one is from the recovery section.
  • The second option is to use the Internet recovery option.
Very simple, because in all these processes we must have an Internet connection. If we always have an Internet connection, there is no problem, but what if it is not so or is too slow? There are two options for this: through a tool that we can download from the Internet or directly using the tools included in the system.

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Select Disk Utility from the Mac OS X Utilities panel and click
"Continue".

Select a drive or partition from the list on the left and open the First Aid tab.

Click Repair Disk.

But first, let's prepare everything we need. Don't worry, it can be downloaded again. The system will start loading. As we already said, there are two options. If he doesn't find it, he will ask us for its location and we will need to indicate it. We choose to create a boot disk. We accept and are ready, the application erases all content, formats and creates an installer.

The second way is to use the system tools. Once the process is complete, go to the "Recover" tab. Now we click on the "Restore" button located in the lower right corner and the process begins. But in some cases, some people choose to do things differently.

If Disk Utility can't fix the disk, try as much as possible
save the information in a backup copy and follow the instructions in the section
“Reinstalling Mac OS X and Apple Software” on page 97.

Information about Disk Utility and its settings can be found in the Help
center, or you can open Disk Utility itself (in the Utilities folder
in Launchpad) and select Help > Disk Utility Help.

In addition, it brings back a new, clean computer feeling, ready to be refilled with the products of your new activities and their inseparable content. It is also a good guide for accessibility in case of maintenance or problems. Not only for the installation process itself, but also for reorganizing your environment after completion. Currently, the easiest way is to use the recovery features built into the operating system, but options for creating recovery and installation disks are also available.

Installing Mac OS X Yosemite from scratch

In the list on the left, the boot disk in the machine is available for selection. By default, the drive will be formatted as quickly as possible; Any choice beyond this could make the process take hours, so only use these options if necessary.

Restoring information using a backup copy
Time Machine

If you have previously created Time Machine backups, you can use
"Recovery" utility restores all the contents of the computer
to the state in which it was at a certain point in time
in past.
Use a Time Machine backup only for recovery
information on the computer from which the backup was created.
To transfer information to a new computer, use the Assistant
migration.

The process time will depend on your broadband connection and the machine will restart during the process. After downloading the utility, open it from the disk image itself and select one of the available disks to make your media. Or, alternatively, don't want to update?

  • First, you need to download.
  • Now it's time to install the system, this step is also very simple.
Only then will you be able to safely navigate the system.

As a rule, developers release automatic updates, but this is not the rule. Do this at least on the software that is most important to you. This is important to avoid losing productivity. This is because you will still have software updates after installation.

If the backup is on a Time Capsule, make sure the Mac Pro is connected
to the same Ethernet or Wi-Fi network. (To connect to a Wi-Fi network, follow
instructions on page 95).

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There is a problem - there is a solution

In the Mac OS X Utilities panel, select Restore from Time Backup
Machine" and click "Continue".

Old operating system = Bad thing

Unfortunately, this is very common. In the next lesson you will see step by step to do this safely and automatically. What do you think happened? Moreover, many third parties have stopped providing software updates that are compatible with older operating systems.

Browsers and plugins are commonly used as a means of infecting computers, so it is extremely important that these programs, along with the operating systems that run them, are not updated. Using this update path will allow you to save the contents of your hard drive.

Select the drive where the Time Machine backup is located, and then
follow the instructions on the screen.

Reinstalling Mac OS X and Apple programs

There are times when you need to reinstall Mac OS X and Apple programs.
When reinstalling the system, you can save all files and settings.

Important.

You can also reinstall and restore from the Mac OS X Utilities panel

If not, let them know that it's time to seriously consider purchasing a new computer. You will be prompted to select a boot disk. . If you have before reinstalling or if you do so, your computer will restart and display the installation assistant.

Indeed, on these models, the recovery partition is present on the source disk, and many cloning programs do not take it into account. The first two are used to restore your system and data. The first method is recommended if the recovery partition is already on the drive or you have a high-speed Internet connection. The second method is recommended if you do not have access to the Internet.

Mac OS X Lion Server software, if installed on your
Mac Pro.

Make sure your Mac Pro is connected to the Internet via Ethernet or Wi-Fi.

"Continue".

When prompted to select a drive, select the current Mac OS X drive
(in most cases this is the only option available).

To install additional software, click
"Tune".

Method two: Recovering from the recovery partition

Attention.

Choose between two systems at startup

If necessary, here is the procedure for installing the utilities. Everything for a successful migration. You don't lose your data, your passwords, or your apps. In about half an hour you will be at home with a new interface! This may happen because a hard drive structure error will cause the update to fail and therefore require a full format.

The installation said correctly

Here you are in your new home! To retrieve data from your old computer or back up after a clean install.

Click Install.

You can install Mac OS X without deleting the entire contents of the disk (and
existing files and settings are preserved) or clear the disk first (if
this erases all your data) to prepare the computer for reinstallation
Mac OS X and programs.

Reinstall the latest system

This page is “illustrated” with a video. It therefore depends on independent updates other than the evolution of the operating system. Paste it and follow the instructions below. First, disable some accounts and services first.

Reinstall the original system

These explanations also apply when you want to do some spring cleaning and head out onto a brand new foundation.

Internet connection, if nothing

Then, are you ready to reinstall the machine "like new"? This first condition is not exclusive, but we prefer to have the latest version and simpler process first. Release him as soon as the apple appears. Specify the name of the boot disk and click "Clean up". Prepare some coffee or hot chocolate and let it go.

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There is a problem - there is a solution

After reinstalling Mac OS X, you can go to the Mac App Store and reinstall
Download the programs that came with your Mac and other programs
that you purchased from the Mac App Store.

before proceeding with software recovery. Apple
is not responsible for possible loss of data.

Finally available to the general public starting today. This release marks a turning point for the system, which becomes completely free. After downloading, a window will automatically open asking you to begin installing the system. Once you've made sure you've backed up, you can continue.

You will need to accept the new license agreement associated with it, select the hard drive to install the update on, and enter the administrator password for your computer. After this preparation step, the computer will automatically restart and begin installing the system. This is the longest step as it will take about 40 minutes during which the machine will not be used. New reboot and here you are at the last step.

Restoring your computer to factory settings

Restoring your computer to factory settings deletes everything on it.
yes (accounts, network settings, files and folders). Before recovery
be sure to create a backup copy of the files you need: copy
them to another disk. Make a note of your network settings so that after you reinstall Mac OS X
it was easier to reconnect with her.

As with any maintenance operation, follow the instructions carefully. Everything will be erased and you will start with the factory configuration. If successful, you will see “Launch Internet Recovery” on the screen. This may take a while or in French as in this case there may be "Running Internet Recovery". This may take a long time. This is probably the most difficult step! You must wait until the original operating system loads.

Installation from recovery partition

Logically, you must select the installation language. It will be French without hesitation that you select using the trackpad or keyboard arrows. Finally, close the format window. The technical difference between the two models is that there is no access to the battery and hard drive on the new model, and the bottom is completely screwed down. Why change your hard drive?

Make sure you are connected to the Internet via Ethernet or Wi-Fi.
(To connect to a Wi-Fi network, follow the instructions on page 95.)

In the Mac OS X Utilities panel, select Disk Utility and click
"Continue".

Select the drive in the list on the left and open the Erase tab.

From the Format pop-up menu, choose Mac OS Extended (Journaled)
enter the drive name and then click Erase.

After erasing the disk, select Disk Utility > Finish
Disk Utility."

In the Mac OS X Utilities panel, select Reinstall Mac OS X and click
"Continue".

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There is a problem - there is a solution

Follow the instructions to reinstall Mac OS X and Apple programs
Mac OS X installer.

After restoring Mac OS X and Apple programs, you can, at your discretion,
Restore necessary files and programs from a Time Machine backup.

Most Mac users have made the transition to the new macOS Sierra operating system without any problems, but there are some who have encountered problems. If your computer has problems at the software level, it makes sense to reinstall the OS. This article will discuss a method for reinstalling macOS Sierra that does not involve completely formatting the Mac and deleting user data. That is, this is not a “clean” installation of the system, in which all data is deleted.

Even though this is simply a reinstallation of macOS Sierra and won't affect anything else, theoretically there could be problems along the way. Therefore, we highly recommend that you back up your Mac.

How to reinstall macOS Sierra

Step 1: First of all, back up your data on your computer.

Step 2: Restart your Mac, press and hold COMMAND + R at the same time right after you hear the boot sound. This will put the computer into recovery mode.


Step 3: In the macOS Utilities window, select Reinstall macOS.

Step 4: Click Continue and follow the onscreen instructions.


Step 5: In the drive selection window, select your hard drive on which macOS will be installed and click “Install.”


Once the macOS Sierra reinstallation process starts, the screen will turn black and a white Apple logo will appear with a progress bar and the amount of time remaining until completion.


When finished, macOS Sierra will automatically launch normally. Your account, data, applications and settings will remain in place. The reinstallation is on a storage device, which may affect performance, but when completed, the Mac will work as before.

Some users have noted that reinstalling macOS Sierra helped solve many problems that arose after the update. Therefore, it is absolutely not necessary to resort to extreme measures and perform a “clean” installation.

Sooner or later the day comes when you need to reinstall the Mac OS operating system on your MacBook PC. This task is no more difficult than reinstalling Windows. This is what we will talk about.

operating system on MacBook

The reasons for reinstalling the MacOS operating system on a Mac computer are as follows:

  • Damage or wear of the built-in storage device (HDD);
  • selling or donating a MacBook to another person;
  • “moving” to another MacBook (a newer model, but maintaining the previous version of the MacOS system);
  • transferring data to Apple gadgets or to another computer.

What happens when reinstalling MacOS:

  • “from scratch”, including formatting the built-in disk;
  • reinstallation “on top”, preserving personal data and applications (macOS update).

For example, using the MacAppStore, you can upgrade your version of OS X Lion and OS X Mountain Lion to a newer version - OS X Mavericks.

Here are the steps to follow when selling or transferring your Mac to someone else. It deserves special mention.

  1. Backing up personal data from a MacBook to a separate media or cloud service.
  2. Disabling special services and functionality that manage data copying and transfer.
  3. Erase all personal information from the disk.

Attention! Before you start reinstalling MacOS on your MacBook PC, take the trouble to save all your data on an external drive! This will be discussed first.

Backing up your data using Time Machine

The Time Machine application is designed to backup personal files from a MacBook and restore them back to it. But it requires external USB drives (HDD, SDD drives) formatted in MacOS Extended or Xsan - FAT/NTFS file systems designed for Windows and Android are not supported. If the disk was previously formatted in FAT/NTFS formats, the MacBook will not accept it if you refuse to reformat it to your liking.

The Time Machine application is launched from the MacOS system preferences in the Apple menu. When you connect an external hard drive, a corresponding notification will appear.

Do you really want to destroy all data recorded on this drive in a different format?

If the external drive has already been formatted, the Time Machine application will give the go-ahead for its use. Confirm your request.

Do you really want to copy your data to this drive?

If Time Machine does not show disk selection, do the following.


Interestingly, backups in the Time Machine program are fully automated - the backup copy is “refreshed” hourly, and their storage is organized, so you won’t get lost in them. In addition, copying is also possible to an Apple server (like iCloud) and to local network storage that supports the Apple File Protocol. All this often helps, if you need to reinstall MacOS, to avoid losing precious working time.

After copying all your data, you can start reinstalling MacOS.

Reinstalling MacOS on Mac

There are several ways to reinstall the MacOS operating system on a MacBook: a “clean” installation from a flash drive, installation “over” a previous version (updating from MacAppStore) and restoring MacOS from a backup.

How to reinstall Mac OS from an installation flash drive

The preliminary steps are as follows.

  1. Download the Mac OS X installation image from the Mac App Store or third-party sites.
  2. Once the download is complete, right-click on the downloaded file and select “Show package contents.”
  3. Go to the /Contents/SharedSupport/ folder, copy the InstallESD.dmg file to a safe location on your disk, and mount it to your MacOS desktop.

We will need the Disk Utility application included with MacOS. The next steps are as follows.

  1. Launch MacOS Utilities and select Disk Utility.

    Select MacOS Disk Utility

  2. Insert the USB flash drive that is intended to be installed.
  3. Launch the “Our media” component (the name of the flash drive will appear in the title) - the “Partition the disk” tab will open.

    Give the drive a name that makes it easy to find

  4. Select the partition layout and under the Options button, check “GUID Partition Scheme.”

    Click OK button

  5. Open the "Recover" tab. Make the MacOS image the source, and the flash drive the “destination”, and click on the “Restore” button.

    Specify what and where to copy

Disk Utility will create an installation flash drive automatically, and it does this operation quite reliably. When copying is complete, Disk Utility will notify you.

Congratulations! The MacOS installation flash drive has been created! You can restart your MacBook. Preparing to install MacOS is as follows.


All! MacOS installation has started. The MacOS operating system will install automatically - this will take 30-100 minutes, depending on the performance of your MacBook. After it, your PC will be immediately ready for use.

How to install the system without formatting the internal drive

Installing MacOS without erasing the disk means downloading and installing MacOS updates directly from the MacAppStore. An installation flash drive is not needed here. This is reminiscent of updating iOS on smartphones and tablets over the air. This method is good for those who once bought a MacBook - and are not going to change it, but, on the contrary, will work on it for many years, because MacBook computers, like Apple iDevice gadgets, are very high quality, reliable and convenient.

Before updating, check whether your MacBook meets the hardware requirements of the new version of MacOS - otherwise it will slow down.

Not every previous version of MacOS can be updated to the desired version. So, if your MacBook is running macOS Snow Leopard (10.6.8) and your MacBook will run macOS Sierra, first upgrade to macOS X El Capitan.

The version of MacOS Sierra is taken as an example. Other copies are searched for and “installed” in exactly the same way. Your actions are as follows.


If you have OS X El Capitan 10.11.5 (or more recent), the macOS Sierra version downloads silently. You will then be prompted to install this version.

Click on the install button

During the installation of MacOS, the PC restarts several times. If this version does not suit you (the performance of the MacBook has dropped), “roll back” to the previous one (for example, OS X El Capitan), with which the PC performance was very satisfactory.

Restoring MacOS from a backup

For example, we take a “rollback” from MacOS Sierra (10.12) back to OS X El Capitan (10.11) or OS X Yosemite (10.10). Let's say there are backups made in the Time Machine application before installing MacOS Sierra.

Important! You can restore a MacOS system from a backup only on the same MacBook. Trying to transfer your copy of MacOS with data to another PC in this way is useless. Use other methods.

  1. Connect your external drive to your MacBook and save your existing files to Time Machine, naming the new copy MacOS Sierra.
  2. Open your previous copy of OS X Yosemite with Time Machine on a different drive after connecting it to your MacBook.
  3. Restart your MacBook while holding down Command+R on your keyboard. The familiar MacOS recovery menu will open.
  4. From the OS X Utilities menu, select Restore from Time Machine Backup.
  5. Once in the “Recover from Time Machine” recovery window, click on “Continue”, and then specify the source - the disk with the OS X El Capitan “backup”.
  6. The saved copy should be: In the case of OS X El Capitan, the MacOS version should be 10.11.x. Click the Continue button. Specify the installation disk to restore from a copy, click on “Restore”.

Ready! The OS X El Capitan version will be reinstalled.

Transferring a copy of the operating system and your data to another MacBook

Go to Programs/Utilities and open Migration Assistant. The structure of your files and folders will be preserved.

Click to continue

When running, the application requires closing all other running programs.

If both computers are working, but you still want to duplicate your version of MacOS and all data on the second computer, connect the computers to each other using a LAN cable via a Wi-Fi wireless network. Connecting directly using a Thunderbolt or FireWire cable will require running your previous Mac in backup mode, which will make the Assistant experience a little more complicated. However, both methods work clearly. You can connect an external disk with a backup copy to the new PC instead of the previous PC - in this case, the operation of the Assistant on the new PC will not change significantly.

So, the procedure is as follows. As an example, we take the normal operating mode of a previous PC with “Assistant”.


All! The copy session has started. This can take anywhere from 30 minutes to two hours, depending on the amount of data and the performance of both Macs.

Problems encountered when reinstalling MacOS

Problems when updating or “rolling back” may be as follows.

  1. No recent backups. You once disabled backup yourself. Copy your files now to avoid losing them by starting the process manually. Enable backup.
  2. An error occurred during the next backup or when restoring personal data from a previous copy. The external drive that was previously recorded is unsuitable for further use. Contact an Apple service center or certified computer repair shop to restore your data. This procedure is not free.
  3. Error during the next MacOS update. Your Mac PC may no longer be supported. This happens once every few years. You will continue to use the current version of MacOS until you replace your Apple PC.
  4. The computer began to work noticeably slower than before the update. The minimum system requirements of the next new version are equal to or exceed the technical specifications of your PC. “Roll back” to any previous version of MacOS. Typically, Apple tries to prevent this from happening - it simply stops supporting older computers, just as it is no longer possible to install iOS 10.x on iPhone 4x devices.
  5. After several active years, your PC suddenly began to freeze despite the fact that you did not update MacOS. Maybe it's time to replace the internal HDD/SSD drive? Try to back up your important data before replacing the internal drive - while something is still being read from it.
  6. It is impossible to “roll back” to one of the previously installed versions of MacOS. The “rollback” must be done gradually. If there are no previous backups, download a new “image” and “roll back” to this version first, and then repeat the “roll back” to an even earlier version of MacOS.

Video on the topic

Reinstalling MacOS - “on top” or “from scratch” - is not difficult. It is only important to secure your data. This is a real way to extend the life of your beloved MacBook for another number of years. You will succeed!

Quite often, Mac users are faced with the following problem - how to return the computer to factory settings, resetting all user information, and reinstall the operating system “cleanly”. Instructions for this process are presented below.

The Mac, like most other Apple devices, is designed for personal use. This means that usually computer owners fine-tune the system for themselves and another user will not be entirely comfortable working with it. If there is a need to completely get rid of existing data and settings, then you need to follow the simple steps described below.

Clean installation of macOS: preliminary steps

IMPORTANT: Before a clean installation (reinstallation, flashing, factory reset) of a Mac, be sure to check:

  • Is your Mac tied to your Apple ID and not some other one?
  • Do you remember the credentials (username and password) of your Apple ID. You can check, for example, by logging in (from your computer).

The fact is that if the Find Mac function was activated on the Mac (located along the path: System Preferences → iCloud → Find Mac), then after reinstalling the system (resetting to factory settings), the system will ask you to enter the Apple ID to which the device is linked .

  • How to find out (see) which iPhone, iPad, Mac are linked to Apple ID.
  • How to recover (reset) a forgotten Apple ID password for iCloud, iTunes and App Store.
  • What will be deleted if you sign out of iCloud on iPhone, iPad and Mac?

How to reset Macbook, iMac, Mac mini, Mac Pro to factory settings (how to reinstall macOS)

1. Make sure you have an Internet connection (for later installation of macOS), as well as an electrical connection in the case of a MacBook.

Attention! Further actions will lead to the complete deletion of ALL data on the Mac - save the necessary information on external media in advance;

2. Restart your computer (or turn it on if it was turned off) using the  menu → Reboot;

3. During the reboot process, press and hold the key combination that suits you best:

⌘Cmd + R– installing the version of macOS that was running on the computer before problems arose. Those. your Mac will install exactly the same version as before.

⌥Option (Alt) + ⌘Cmd + R– Update to the latest version of macOS that your Mac is compatible with. For example, if the Mac was running High Sierra, and the breakdown occurred after the final build of macOS Mojave was released, the system will download Mojave from the Internet and install it.

⇧Shift + ⌥Option (Alt) + ⌘Cmd + R– installation of the version of macOS that was originally installed on the computer (or the closest available version to it).

Note: macOS Sierra 10.12.4 or newer required.

4 . Then the window “ macOS Utilities"(on versions lower than macOS High Sierra may be called "macOS Utilities"). Here you need to select " Disk Utility" and click " Continue";

Checking and fixing boot disk errors (recommended)

1 . In Disk Utility, select your drive from the menu on the left (usually a Macintosh HD, it's at the very top).

2 . Click on First Aid.

3 . Click Launch. The application will check the boot disk for “health status”, i.e. functionality and correct existing errors. This process may take some time.

4 . Once the scan is complete, click Finish.

Erasing the boot disk

1. In the Disk Utility application, select a verified startup disk, go to the “Erase” section (at the top of the screen);

2. On the menu "Format" select APFS (for computers with macOS Sierra installed and an older version of the OS, select Mac OS Extended) and press " Erase";

3. Once the disk formatting process is complete, click " Complete" to exit Disk Utility.

Reinstalling the macOS operating system (factory reset)

Reinstall macOS using the appropriate item (screenshot below) and follow the instructions. The latest version of macOS will be downloaded from the Internet and the macOS reinstallation process will begin. During this time, the computer may restart.

Note: If you're installing from scratch, you'll have to configure your Mac and program settings all over again.

Based on materials from yablyk

Computer Apple is a very reliable machine, but sometimes problems with the operating system happen to it too. If something breaks and your Mac behaves very strangely - use a great Apple tool called Recovery.

An “emergency” system reinstallation is possible on Macs running version 10.7 Lion and older. While in this mode, you connect your computer to the Internet and download the full version of the operating system from there. In this case, there is no need to make an installation disk (convenient, since most Macs today are offered without an optical drive, but a bootable flash drive).

Options

OS X system utilities include more than just reinstallation Mac OS X by downloading it from the Internet. There are three more possible actions:

  • Restore Mac from Backup Time Machine(if you have one).
  • Disk repair Disk Utility.
  • Online support via Safari.

It is recommended to first check the damaged disk using a special Apple utility (the second method listed above). If it doesn’t help, proceed to recovery - either through or through reinstallation. In this article we will look at the option of downloading from a copy of OS X from the Internet and then reinstalling the system.

How to enter Recovery mode

  1. Make sure that your Mac can connect to the Internet via wireless connection WiFi. It is advisable to use a closed home network rather than an open public one.
  2. Shut down (I mean turn off) your Mac. Click on the apple menu and select Switch off… If the computer does not respond (this is possible if the system is frozen), hold down the power button. After a few seconds, your Mac will turn off.
  3. Wait 30 seconds (so as not to damage the computer's hard drive by turning it on quickly).
  4. Turn on your Mac by pressing the power button. Important — press immediately two keys - ⌘Cmd and R! After some time, the menu described above will appear with utilities for OS X.

How to reinstall OS X via Recovery mode

Connect to a Wi-Fi network. To do this, click on the wireless network icon in the upper right corner, select the desired network and, if necessary, enter the password. Next, you can start downloading the software - the most recent version of OS X. It is worth keeping in mind that this file is quite large in size, and downloading it will take a lot of time - from several tens of minutes to several hours. Agree to install OS X and click Continue, follow the instructions that appear on your Mac screen.