Need to Update OS from High Sierra to Catalina

A MacBook Air from 2017 can upgrade to macOS Big Sur.

Open your Safari browser and click on the link below.

How to upgrade to macOS Big Sur - Apple Support

Before upgrading make a full back up of your Mac.

Check that third party apps you use have updates available for the new OS.

https://roaringapps.com

Check that your printers/ scanners etc have updated drivers and software available for the new OS.

Connect your mac to your router via cable rather than rely on WiFi.

Do not use your mac while it is downloading

and do not use any other devices that share the same internet connection.

If the App Store says ‘Open’ then it is detecting a previous download of the install app

go to the Applications folder locate Install macOS Big Sur.app.

Move it to the Trash, empty the Trash.

Restart, click on the link again, the App Store should say ‘Get' or 'Download'.

If you are considering upgrading to Big Sur be warned it does not support 32bit apps.

Your Mac is probably running 32bit apps and these will need to be updated to 64bit apps,

some updates may be free, some may be paid. Use this app to discover which apps you have

are 32bit, https://www.stclairsoft.com/Go64/ then contact the developers of the software to see

if they are offering 64bit updates.

See How to get old versions of macOS - Apple Support

Download the installer using Safari.

Have a backup before the upgrade.

Ensure all apps are 64-bit. 32-bit apps will need updates, upgrades, replacement, or retirement. You can find the older 32-bit apps using the Go64 tool.

Ah, okay, I thought you were looking for Catalina. If you want the current Big Sur, that was also linked in the previously-linked article, and here’s that link extracted:

How to upgrade to macOS Big Sur - Apple Support

pravin217 wrote:

Hi ,

I am Using MAC Book Air 2017 and I want to update my OS from High Sierra to Catalina but there is no option to update the same pls help the same

If Catalina is what you want as per above follow direction provided in earlier posting.

If one what Big Sur - also follow instruction in previous posting

Tips How to Upgrade to Big Sur