High Sierra Download Always Fails

1. Check Your Internet Connection: Ensure that you have a stable and reliable internet connection. Slow or intermittent connections could result in download failures. Consider using a wired connection if you're experiencing issues over Wi-Fi.
2. Free Up Disk Space: Make sure you have enough free space on your Mac's hard drive to accommodate the download. macOS updates require a significant amount of space. Delete unnecessary files or applications to create more space.
3. Restart Your Mac: Sometimes, a simple restart can resolve temporary glitches. Try restarting your Mac and then attempt to download macOS High Sierra again.
4. Try Different Download Times: Apple's servers can become congested during peak download times. Consider trying the download during off-peak hours when server traffic might be lower.
5. Use a Different Network: If possible, try downloading the update from a different network, such as a friend's house or a public Wi-Fi hotspot. This can help determine if the issue is specific to your network.
6. Clear App Store Cache: Launch the App Store, and while holding the "Option" key, click on the "Store" menu at the top and select "Clear Cache." This can help resolve issues with the App Store app.
7. Check Apple's Server Status: Occasionally, Apple's servers may experience downtime or issues. You can check the status of Apple's services by visiting Apple's System Status page on their website.
8. Download from Apple's Website: Instead of using the App Store, you can try downloading macOS High Sierra directly from Apple's official website. Go to the macOS High Sierra download page and follow the instructions there.
9. Update via macOS Recovery: If the standard download isn't working, you can try updating using macOS Recovery. Restart your Mac and hold down Command + R until you see the Apple logo. From there, you can choose to reinstall macOS High Sierra.
10. Contact Apple Support: If none of the above steps work, consider reaching out to Apple Support for further assistance. They can provide more specific guidance based on your situation.

Remember that macOS High Sierra is an older version of macOS, and Apple may have phased out support for it. If you're encountering persistent issues with downloading or installing it, you might also consider upgrading to a more recent version of macOS if your hardware supports it.

Two days ago when helping another user.

Part 1 of 2

On a 2011 Mac Mini running High Sierra 10.13.6 - I re-downloaded the Full Version of High Sierra

As it stands right now, the Install High Sierra is still sitting in the Application Folder of that machine

How to get old versions of macOS and verify what version this computer Qualifies to install.  For Best results use Safari to commence the download as Others may not work.

Safari will open a redirect and open the Apple Store where the download can commence.

Part 2 of 2

Now this s disturbing " Purchased page to try again." High Sierra doesn't show up in my purchased tab "

This will have to be performed from a Qualifying Computer to run the version of macOS.

Example : High Sierra would have to be done on a computer that Qualifies to run High Sierra

Notation: If the computer being used to perform this action is Too New or Too Old to qualify to run the version of macOS - this computer can not be used.

Alternative is, to gain access to a Qualifying Apple Computer from a family member, friend or associate.

The 40MB "installer" is what we call a stub installer. You need to actually run that stub installer which will then download the rest of the macOS installer until you have about a 6GB app or 12GB depending on the OS being downloaded (Monterey will be the larger one). Once the stub installer has finished downloading the rest of the actual installer, you can quit the app and follow the instructions in the Apple article to use the command line to create the USB installer. I have found that sometimes the installer will automatically begin installation once the download is complete, so pay attention to when the download is about to complete so you can quit the installer before it reboots the system. We have no idea why sometimes you only get a 40MB stub installer while other times you get the full 6GB or 12GB installer. I have had it give me a full installer one time, then the next time just the stub all on the same computer and same running OS & same OS download.

Your other problem is likely Avast and any other anti-virus apps, cleaning/optimizer apps, or third party security which is installed since these types of apps interfere with the normal operation of macOS. Browser extensions & plugins can also interfere with downloads & accessing web sites.

If the Mac needing the OS has ever had macOS 10.12.6+ installed at some point in the past, then it should be capable of using Internet Recovery Mode (Command + Option + R) to access the online macOS installer (this key combination will give you the most recent OS which is compatible with that Mac...or use Command + Option + Shift + R to access the online installer for the OS which originally shipped with that Mac although this may require extra work due to expired certificates with the installer). Even if the OS you want at the moment is not available directly through this method, at least you now have a bootable Mac where you can create your bootable macOS 10.13 USB installer.

Here is an Apple article with instructions for creating a bootable macOS USB installer:

Create a bootable installer for macOS - Apple Support

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