How to fix
“An Error has Occurred” when downloading macOS High Sierra
on Windows

Hi, I can't download macOS High Sierra as it shows "An Error has Occurred" message. I have tried to restart the download, but the notification persisted. What should I do? Are there any ways to fix "An Error has Occurred" when downloading macOS High Sierra? Thanks in advance!

macOS High Sierra is an operating system for Macintosh[ref en-1] computers which are developed by Apple Inc. Users who are running earlier versions, like Yosemite, El Capitan, or Sierra might want to update their operating systems to the latest available one. 

Note that it is essential to keep your operating system up-to-date in order to eliminate vulnerabilities that might be used in cyber attacks. Additionally, updates are designed to fix various bugs and errors that may deteriorate your experience with the computer. 

However, people have recently reported on "An Error has Occurred" message when trying to download macOS High Sierra. This notification appears when people are trying to update their operating systems and stops the procedure. Even though the exact cause of "An Error has Occurred" High Sierra error is not discovered yet, experts identify several potential culprits including the following:

• Damaged files during the download;
• Third-party app interference during the download;
• Presence of potentially unwanted programs (PUPs)[ref en-2].

Our IT professionals are eager to help regular computer users fix "An Error has Occurred" when downloading macOS High Sierra to ensure that people can update their operating systems successfully. We have attached guidelines showing the steps which may fix "An Error has Occurred" error below. 

Get rid of "An Error has Occurred" macOS High Sierra error

Before you try to fix "An Error has Occurred" when downloading macOS High Sierra, you should scan your computer for potentially unwanted programs (PUPs). There are cases when people can't update their operating systems because PUPs are interfering with essential computer processes. For that, use [rev id="MacKeeper"].

NOTE: You must back up your files before proceeding with the instructions below. 

Method 1. Reset settings stored in NVRAM and PRAM

In some cases, various MacOS errors may appear due to misconfigured Date & Time or other settings. Mac computers store these parameters in Nonvolatile Random-access Memory (NVRAM)[ref en-3] and Parameter RAM (PRAM). Thus, resetting them might help:

1. Shut down your computer;
   

   

2. Turn it on and immediately press and hold Option + Command + P + R buttons;
3. Hold them for about 20 seconds;
4. Once the computer plays the startup sound twice, you can release them;
5. Let Mac restart and retry to download macOS High Sierra.

Method 2. Boot your computer from the Recovery HD

1. Turn on your computer and hold Command + R keys;
   

   

2. Once Utility Menu opens, select Reinstall OS X;
3. Click the Continue button and follow the on-screen instructions;
4. Try to download High Sierra update.

Method 3. Create a new user account

1. Open System Preferences and go to Users & Groups;
2. Click on the Lock icon and enter Admin username and password to enable changes;
   

   

3. Click on the Add (+) button and set up a new Admin user account;
4. Log out of the current account and log in with a new Admin account;
5. Try to download macOS High Sierra and see if the problem persists.