dosdude1

It’s unfortunate that Apple hasn’t made special dmg downloads to allow you to download Mavericks. My understanding of the App Store link to buy Mavericks is that it only loads of your computer is “old enough” or running 10.7 or 10.8 already. It was the first “free” update, if I recall correctly, and like the updates that followed (10.10, 10.11, 10.12) there were restrictions so only specific computers could download it running specific versions of macOS. That’s why they needed special download links, I think?

I’ve had the most success installing older copies of macOS by using the Recovery Mode to install the copy of the OS that originally shipped, then updating from there to whatever specific version I needed.

Remember: you can’t install a version of macOS that is older than the hardware - meaning every Mac sold has a version that it shipped with and that’s the minimum version required. From there you can choose which updates to install… it’s a long, slow process.

Also note, just as hardware has a minimum OS version it generally has a max version too: I once tried to install a newer copy of macOS on unsupported hardware and was frustrated that the Next button was greyed out or the installer wouldn’t boot. So I used a different Mac to install it, then copied the hard drive. Still didn’t boot. Very frustrating. Turns out I needed a patch to get it to work: http://dosdude1.com/software.html For Big Sur there a set of patches too, but I imagine as time goes by it’s harder and…

Apple doesn't want to give you a choice but you can still do it:

1. Use some mac to download an older OS installer. The links are hidden but you can find them in some forums etc.

2. Create a bootstick - either manually or with software like dosdude's really nice patchers (find them here: http://dosdude1.com/)

3. Backup your stuff (not only time machine as it would reinstall the new version of macos again) and install the old macOS to get your apps and files back on it

This is something I really hate about Apple - why can't they just provide some official download links that keep working?

With Apple I have a love-hate-relationship because some products (MBP until 2016/17, iPhone 5s/SE) and software (keynote, pages, lot of parts of the OS) are awesome while their software policy and planned obsolescence screws you hard if you just follow their lead as a simple user.

You always have to take care not to update too early, use workarounds to integrate devices with different Apple software (like with airdrop) and if you brick devices there is few ways getting back to business (no helpful error messages like the icons they show on boot when something goes wrong or messages from their system diagnostic like "HDD is damaged" while it's just the cable).

Surprisingly, you can get the current macOS Catalina running on 2008 Mac(Book)s with the tools published by dosdude1 and other contributors [1].

macOS Catalina will actually still get security updates for two years after Big Sur is released (they support macOS releases three years after release). So that's until ~late 2022, a pretty long run for that 2008 hardware until you have to go to Linux or Windows for your patches.

It looks like Big Sur has a hard requirement on Metal (at the moment at least), which kills all pre 2012 Macs [2] that were still running Mojave/Catalina using OpenGL.

[1]: http://dosdude1.com/catalina/ with various important caveats of course, depending on your model.

[2]: Metal is supported on GPUs since Intel Ivy Bridge and Vulkan compatible AMD/Nvidia hardware. The Mac Pro 2010 is the exception since you can upgrade its GPU to a Metal compatible one.

Super, super easy. Linux-distro-install level easy.

Since Catalina randomly decided to destroy access to about 1/3rd of my software (I rely on old-school music plugins that won’t be updated) - I’m gonna link you here to the Mojave tool:
http://dosdude1.com/mojave/

This is not my tool, it does require a Mac to use, in order to create the USB boot key you put in your PC.

I have successfully patched about a dozen ThinkPads and Dell computers with this.

Due to the ThinkPad’s popularity - support for virtually every unit that can support it hardware-wise exists. If you have any issues, there’s a great community around it, and personally, after patching, I don’t even worry about .x upgrades anymore and leave auto-update on - that’s how far it’s come.

I literally prefer the Lenovo to the Apple hardware.

If you don't mind stranding from the 100% stable roads, you can install Mojave on your macbook using this patcher: http://dosdude1.com/mojave/

Personally I am running Mojave on a late 2009 macbook pro and it still works amazingly well. Transition from Mojave and especially the new XCode are also way faster than previous iterations. There are caveats though, as the processor in my computer is too old, I had to hack homebrew to compile everything from source.

(Also, using the patcher does not hinder my ability to push updates to the App Store or use iMessage, if that is a concern)

If you held on to that machine for a few more years it would have been dropped by OS X Yosemite, but then hilariously still supported by essentially making the machine a Hackintosh!

https://forums.macrumors.com/threads/2006-2007-mac-pro-1-1-2-1-and-os-x-yosemite.1740775/
https://forums.macrumors.com/threads/2006-2007-mac-pro-1-1-2-1-and-os-x-el-capitan.1890435/

A similar situation played out when macOS Sierra dropped support for 2008–2009 models that can be re-enabled in a patch:

http://dosdude1.com/sierrapatch.html
http://netkas.org/forum/index.php?topic=852.0