You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

Update to OS X Big Sur?

How do I update my iMAC (21.5-inch, Mid 2011) with OS X Yosemite 10.10.5 to the OS X Big Sur 11.5.1?

iMac Line (2012 and Later)

Posted on Aug 6, 2021 6:09 AM

Reply
2 replies

Aug 8, 2021 1:54 AM in response to Updatefromthedarkages

It has been decided by Apple that this computer does not Qualify for the Big Sur upGrade.


The Age of this computer will Govern what newer version of macOS it will Qualify to install. Use About this Mac from the Apple Icon on Desktop - the required Information will be there.


With the above information in-hand - follow this How to get old versions of macOS and verify what version this computer Qualifies to install. Make sure to use Only Safari to commence the download as Others may not work


Make a Time Machine Backup Before attempting. Notation - Mojave is the Last version to support 32 bit applications / extensions and Drivers. Catalina and Big Sur Only support 64 bit and there is no workaround.


Are there any AntiVirus, Disk Cleaner, Optimizers, Un-installers, etc installed which should be removed as per Developers Instructions. They are useless, unneeded, cause havoc and interfere with the normal operation of the OS and may even Corrupt the OS requiring a Reinstallation

Update to OS X Big Sur?

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.