# Troubleshooting OS update and installation issues on Macs

1. OS cannot be reinstalled on erased macOS devices
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### Description

OS cannot be installed back on macOS devices after a device wipe.

### Solution

You may have to install or reinstall the same OS version from scratch to resolve this issue.

#### Step 1: Boot to the Recovery HD

Restart the Mac, and after the chime, long-press the **command** + **R** keys until the menu screen appears. Else, long-press the **option** key until the boot manager screen appears. Then, choose **Recovery HD** and click on the corresponding arrow button.

#### Step 2: Erase the Hard Drive

1. Select **Disk Utility** in the **macOS Utilities** window and click **Continue**.
2. Select the startup volume (generally Macintosh HD) from the *Disk Utility* left panel. Then click on **Erase** in the main window.
3. Input a partition name and set the partition format as **Mac OS Extended (Journaled)**.
4. Click on **Erase** in the pop-up window.
5. Close the *Disk Utility* window and go back to the **macOS Utilities** menu.

#### Step 3: Reinstall macOS

On the **macOS Utilities** window, choose **Reinstall macOS** and proceed with the installation.

 Notes:- An active internet connection is mandatory for OS installation.
- The OS version you are installing now should be the same as the one before the wipe.