The server gave an error during download: 500 Internal Server Error

The Age of this computer will Govern what newer version of macOS it will Qualify to install. Use About this Mac from the Apple Icon on Desktop - the required Information will be there.

With the above information in-hand - follow this How to get old versions of macOS and verify what version this computer Qualifies to install. Make sure to use Only Safari to commence the download as Other may not work

Make a Time Machine Backup Before attempting. Notation - Mojave is the Last version to support 32 bit applications / extensions and Drivers. Catalina and Big Sur Only support 64 bit and there is no workaround.

Are there any AntiVirus, Disk Cleaner, Optimizers, Defrag, VPNs etc installed which should be removed as per Developers Instructions. They are useless, unneeded, cause havoc and interfere with the normal operation of the OS and may even Corrupt the OS requiring a Reinstallation.

https://support.apple.com/en-ca/HT201475 one must upgrade to at least El Capitan then move up to Big Sur. Devil is in the details.

If upgrading from macOS Sierra or later, your Mac needs 35.5GB of available storage to upgrade. If upgrading from an earlier release, your Mac needs up to 44.5GB of available storage. To upgrade from OS X Mountain Lion, first upgrade to OS X El Capitan, then upgrade to macOS Big Sur.

Although it expressly mentions Mountain Lion - Yosemite falls into the same category

Same error here and can't mount external seagate drive or G-Technology drive which are holding the time machine backups.

All I've done since fresh install is update via Appstore and now running safe mode to connect to Appstore and same error.

Since can't mount external time machine backups (which were fine before doing erase/install) not sure what to do.

Now can't use Xcode which is frustrating.

Same question/problem, but from a newly imaged MacBook Pro (Early 2015, Big Sur compatible) with 10.10.5.

I have over 100GB free space. Image was installed from online recovery, so it's otherwise clean.

The Package only creates a New application in the Applications Folder. It is called Install El Capitan. That is the installer on El Capitan and needs to be run.

I had same problem, please see my post https://discussions.apple.com/thread/252913639?answerId=255496827022#255496827022

I had same problem, please see my post https://discussions.apple.com/thread/252913639?answerId=255496827022#255496827022

SOLVED: I updated to 10.13.6 (High Sierra) and then I was able to download Big Sur.

Welcome

I'm trying to update my OS to Macos Big Sur but I keep on getting the message "500 internal server error"