I need to download OS X El Capitan 10.11 but I can't find it--

Sounds like you tried to install an update to El Capitan, for which you would need a previous version of El Capitan installed. You need to download the full El Capitan installer which is approximately 6Gbs, and can be found here,

How to download OS X El Capitan - Apple Support

Depending on your Mac model and its age i.e. if your Mac can upgrade to High Sierra then the App Store will reject your request to download El Capitan as Apple wants you to have the latest software.

if it is definitely El Capitan you want then you may need to find a Mac/ friend that can only upgrade to El Capitan to download it and move it to yours and then install it. Please check back if it is the case...

Hi Eau.

I wrote a reply to the community about this subject and got nowhere with suggestions give. (Not your fault) it just could not be found or work when I did get this link above. However, the whole process was very painful but I continued my quest regardless. Here is how I achieved my goal in the end:-

You cannot upgrade to Sierra or High Sierra as your Mac does not meet the specs:

MacOS Sierra - Technical Specifications

but you should be able to upgrade to El Capitan:

get El Capitan from the App Store

What do you mean you are told you need "this and that"? As long as you meet the specs you should be able to upgrade:

OS X El Capitan - Technical Specifications

Download this app, http://etrecheck.com/ It gives snapshot of what is running on you Mac and can help in diagnosing problems. It is recommended here, it gives no personal information so once run please post the report.

get El Capitan from the App Store

Open Disk Utility Applications/ Utilties and run First Aid does your machine pass the check?

How much free storage space do you have on your HD.

OK so go straight to the App Store click on Featured and then click High Sierra, what do you see, Screenshots please.

I'm having the same problem and for the life of me just don't understand the logic behind all this run around!

I have a 2009 MacBook Pro 17" and been running Yosemite (after upgrading from Leopard, Snow Leopard and Lion)

now with the threat hanging over various software support I wish to up grade to El Capitan (Mac says I can't up grade to High Sierra as my machine maybe too old? I have looked around El Capitan and found it but I'm told I need this and that. What is the story on this and can someone from Apple help apart from getting it from a "Friend"

By this and that I mean some El Capitan requires leopard some requires snow Leopard and some require Lion which I have supersede and now have Yosemite so which download do I need to install the basic El Capitan and where can I find it, because its not in App Store anymore!

Try setting up another admin user account to see if the same problem continues. Also try the Safe Mode.

Isolating an issue by using another user account

Safe Mode - About El Capitan
also Sierra

Safe Mode Startup – El Capitan. also Sierra