I'm struggling to download old Mac OS versions.
I have an old 2009 Mac Pro and the original install disks cannot be found anywhere anymore.
When I go to the app-store on my laptop and try to download it from there I get an error "OS X can't be installed on ... because the version of macOS is too new."
Clearly, the old OS is available for download, but the laptop (Macbook Pro) runs a much newer macOS.
Is there some special trick?
Since you are posting in English you may wish to use the main Apple Support Communities web site: https://discussions.apple.com
Unfortunately the Mac App Store application detects what computer you are using and won't let you download what it considers to be incompatible system versions. If you want to install a system to that Mac Pro you will have to use a computer that will let you download El Capitan onto it or at least boot to an OS on that computer so it can download it directly.
How to download old macOS versions
