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.

2020 iMac: external start up with High Sierra?

Setting up my new 2020 27" iMac with catalina, and am hoping to occasionally use an external SSD, a copy of my previous High Sierra iMac, so can run older programs (looking at you Adobe). Possible?


Thanks! John

Posted on Aug 21, 2020 3:57 PM

Reply
Question marked as Top-ranking reply

Posted on Aug 21, 2020 4:12 PM

No.. High Sierra nor Mojave will boot on an iMac that shipped with Catalina.

1 reply

2020 iMac: external start up with High Sierra?

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