Does reinstalling macOS in Recovery Mode erase everything from your Mac?

This page outlines the steps to recover data from a failing Mac before reinstalling macOS. If you're experiencing the same issue, read on to learn how to export your data from a faulty Mac before reinstalling macOS:

Please provide the English content you would like translated, and I'll promptly translate it into Chinese for you.

"What happens if I reinstall macOS? Will it delete everything?"

"I have an issue with my macOS Catalina, where the login screen doesn't show up. If I reinstall macOS from the Recovery menu, will it delete my installed apps and data? If so, how can I back them up to my hard drive? These apps and data are very important to me."

Reinstalling macOS via macOS Recovery is a quick and easy way to replace your current, problematic operating system with a clean version. Technically, reinstalling macOS does not "erase the disk" or "delete files." Unless you're selling or giving away your Mac, or have a need to wipe data, you usually don't need to erase. Also, if you suspect a problem with your startup disk, you can scan and repair it from the Recovery interface using Disk Utility, which might be quicker and easier than erasing and reinstalling.

How to recover data when you need to erase and reinstall macOS

If your Mac is having issues as described at the start of this article, it's possible that your Mac is damaged and you'll need to consider a full reset by starting up in Recovery Mode and using the Disk Utility there to erase your Mac's hard drive before continuing with the macOS reinstall.

As we all know, formatting Mac hard drive will lead to data loss and make files unrecoverable. You can use Data Recovery Wizard for Mac Pro tool to back up your data first and then recover data from the backup.

Please provide the English content you want translated, and I'll do my best to translate it into Chinese.

Backup Your Mac and Never Lose Data

Back up and restore your MacBook/iMac without using Time Machine, iCloud, or an external hard drive.

This software lets you create a bootable USB drive on another Mac and then restart your Mac from it to continue with the recovery. Especially when you need to recover data from the macOS 10.13 system drive, performing a recovery from bootable media is very safe. Ideal for any emergency, it ensures no further damage to your data!

Follow the step-by-step guide below to learn how to recover data from a non-bootable Mac that needs to be erased and reinstalled. This tutorial will be in two parts: how to create a bootable USB media, and how to recover data from the bootable media.

How to Create a Bootable USB

Step 1: Install and run tools Data Recovery Wizard on another Mac, and choose 'File' > 'Create Bootable USB'. Then select a USB device to make a bootable disk.

Step 2. The program will then begin creating the 2GB partition and saving the boot files. The remaining space on the USB drive can still be used for storage.

Step 3. Once done, boot the damaged Mac from the bootable drive and begin the recovery process. We recommend that you recover your data to an external hard drive.

How to Recover Data from a Mac Hard Drive

Step 1: Search for the Lost File

Select the disk location where you want to search for lost files (it can be an internal HDD/SSD or an external hard drive). Click on the “Search Lost Files” button.

Note: Before you proceed with data recovery, it's recommended that you click 'Disk Backup' from the left sidebar and create a backup of your HDD/SSD to prevent further data loss. After the backup, the software can recover data from your disk image, and you can use the HDD or SSD again.

Step 2: Browse the scan results

The software immediately scans the selected disk volume and displays images, documents, audio, video, and email in the left pane.

Step 3. Select the files and recover them

Click on the data to preview them, and then hit the "Restore" button to get them back.

After the data recovery, you can use Disk Utility to erase your Mac's hard drive, then choose to Reinstall macOS to finish the installation.

View more information about the Mac Data Recovery Wizard

Mac Data Recovery Software allows you to recover deleted files from the emptied Trash, internal/external hard drives, SSD, corrupted or formatted memory cards (including Memory Stick, SD card, CF card, XD and MMC card). Besides, it lets you recover lost Word, Excel, PPT, and more.