Where is Big Sur install file?

Monterey was announced back in June/ July, Apple always removes the previous OS when a new one is

launched. The link you tried earlier has been replaced with a new one, see below.

You can still get Big Sur by opening Safari and clicking on this link,

How to get old versions of macOS - Apple Support

Are you downloading a copy of Big Sur for each machine.

There is no need to that, you can download one copy and create a bootable USB flash drive

installer using the instructions in this article. The USB you use should be 32GBS in size and

from a known respected brand.

How to create a bootable installer for macOS – Apple Support (UK)

When you have created the bootable USB installer, you can use

it to install on any number of macs.

The link that Eau Rouge has provided still works in the UK, see screenshot below.

What is the generic and unhelpful error message.

When opening the link you should be using your Safari browser, I think that is

mentioned a couple of times, once in bold.

Click on the link and go to the download section and click on macOS BigSur 11

this will redirect you to the App Store and will open the Big Sur download page.

It should say Get or Download.

If the App Store says 'Open' then it is detecting a previous download of the macOS Big Sur installer,

move it to the Trash, empty the Trash. connect your mac to your router via cable. Restart your mac

and try again.

This should work for all countries.

The USB Installer is a very good method and use it myself.

Though, if and when the Full Installer of Big Sur is download to one computer - do not allow it to Open and commence the installation. Just Quit it. Now Copy the new Application called " Install Big Sur " to a reliable and large enough Empty Drive / USB. Move the USB Drive from machine to machine can Copy the USB stored Install Big Sur Application to the Applications Folder on each machine. The run the Application "Install Big Sur " directly from within the computer ( As if it was downloaded to each machine )

I am also in the UK and the link works, click on my one and not yours, I said earlier your one will open the old page,

clicking on my link will open the new page which includes Big Sur, as evidenced by the screenshot.

What method were you using to make the bootable installer.

Were you using the official Apple instructions included in the

link I gave you earlier.

I am writing these replies in the full knowledge that the new link works and the method to create a bootable installer works

I make bootable installers quite often.

I would not reply to you instructing you to try something without knowing if my instructions work or without testing

the procedures for myself.

Yes you said thanks, but said the page had not been updated in the UK,

I told you i was in the UK and the link I offered would allow you to download Big Sur..

If you have tried creating a bootable installer many times and it has failed then you must be doing something wrong.

The USB you use might be the problem it needs to be at least 32GBs in size and from a known brand.

The process is simple, I have created many bootable USB installers without issue.

What other methods did you use.

Very much agree with @ Eau Rouge regarding the Bootable Installer - straight forwards as per Apple Createmedia command below

sudo /Applications/Install\ macOS\ Big\ Sur.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled

Where the " Untitled " at end of command matches the Name Given the Destination name of the Drive.

One issue did have, when preparing the Destination drive. If performed - Formatted on Intel based computer - but creating the USB Installer on the M1 ( if applicable ) it would fail. If Formatted on M1 CPU and created Installer on same machine ( M1 ) - presto - worked every time.

The link Eau Rouge has provided, as of 29/10/2021 in Australia, opens in App Store and fails to download with an generic and completely unhelpful error.

This is infuriating, I have a machine I need to recover with a USB drive due to a failed Monterey install.

edit: My question has been answered in the negative. Thank you.