Updating older OS

[atavus]

Being a very limited user, I've never bothered to constantly update my iMac OS - Mail, and occasional shopping works perfectly. But recently I've found a problem with one of the two chess sites I visit. While lichess works as well as ever, Chess.com only works in a limited way - oddly, I can do puzzles, get the page for setting up a game with one of the bots - but the "play" button isn't "live." I even tried switching (reluctantly) from my default browser (Firefox) to Google Chrome. This works - up to a point. It seems that I can't update Chrome (which Chess.com out of nowhere now demand) which needs OS 10.11 - my iMac is 10.10.5. So I seem to be stuck. Is there any way out of this impasse? I've no outstanding updates, so it may be that I've got the most advanced OS I'm ever going to have.

 

[MightyGem]

Which Mac do you have: model and year?

 

[atavus]

It's pretty old by computer standards I suppose. It's an iMac with OS X Yosemite 10.10.5 described as 21.5 inch Mid 2011 - though I probably bought it after that. The OS has automatically updated over the years, until now.

 

[Rodananne]

The last compatible version is macOS 10.13.6 (17G65), High Sierra. Unfortunately you will still be a little limited in app choices, we are up to macOS 15 now but it should run your chess program and Google Chrome. I'm not so sure about Firefox. I have it on a 2010 MacBook running macOS High Sierra but I think the version is unsupported.

To update your iMac from Yosemite to High Sierra see this page from Apple.

How to download and install macOS - Apple Support

Download and install current or previous versions of the Mac operating system on compatible Mac computers.

support.apple.com

Scroll down on the page to the App Store section and try the link for High Sierra first. That should take you to the appropriate page in the App Store to download the installer. It's definitely the easiest way if it works.

Let us know how you go.

 

[atavus]

I really appreciate your help. I got to the High Sierra app store page, but then got a message as follows: "This copy of the Install macOS application is damaged and can't be used to install macOS." (If I actually knew what that meant, I'd probably be disappointed!)

 

[TonyAguila]

I really appreciate your help. I got to the High Sierra app store page, but then got a message as follows: "This copy of the Install macOS application is damaged and can't be used to install macOS." (If I actually knew what that meant, I'd probably be disappointed!)

It’s probably just a failed download. Open your Applications folder and look for a file that starts with “Install macOS …” and trash it. Then launch Terminal.app (/System/Applications/Utilities/Terminal.app). To obtain a full list of available updates, the correct command is

softwareupdate --list-full-installers

A list of available software updates should come up. The one on top of the list will probably be High Sierra. Make a note of the version number. High Sierra should be “10.13.6”

Then enter this command:

sudo softwareupdate --fetch-full-installer --full-installer-version 10.13.6

or whatever numbers appear on the top of the list. Press return, enter your admin password, and the download should start. When done, the installer file should be inside your Applications folder. If the installer automatically launches, abort and restart the Mac, ideally in Safe Mode. Make sure your data is backed up, make a copy of the installer file for future use, and then launch the installer file. Go through the prompts, cross your finders, and good luck.