Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

dozeball

macrumors newbie
Original poster
Hi all.

I'm trying to downgrade back to Catalina 10.15.6, due to a hugely problematic issue I've noticed (FOR ME, PERSONALLY!)....Scrolling or any visual motion causes serious ghosting (2018 Macbook Pro 15)...This never happened in beta 1.

My problem is, now I can not erase my entire drive....Not in recovery mode, which still wants to install Big Sur....Not when booting from a 10.15.6 Catalina USB, nor from Internet Recovery....As soon as I try to erase the drive (not the volume), I get the option to click 'okay', but clicking it actually does nothing....I can click it a billion times, and it still asks me to click okay or cancel.

Is this a startup security issue, or is there any other way that I can erase the entire drive, like in Terminal or in Open Firmware boot mode?
 
I can't help you, but why didn't you install Big Sur on a separate partition? Downgrading major versions have always been associated with problems.
 
You will probably have to partition from Commandline.
Partitioning instead of just erasing might work.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.