*urgent* Downgrading to High Sierra from Catalina??

[Oonagh oh]

Hi. I have made a terrible mistake and I am adamant on fixing it. I have an iMac mid-2011 21.5 inch and I downloaded a Catalina patcher that successfully installed Catalina to my Mac. great. Unfortunately Catalina is extremely slow and buggy on my computer and games that easily ran on the high Sierra version of this computer are now unplayable.

I cannot access the utilities page by pressing cmd and r on restart because I get a white screen when I do so.

I have attempted to make a high Sierra launcher for my iMac which I thought was working until it, didn't.

I am desperate for some advice on this situation.

thank you.

 

[Oonagh oh]

this is what happens when I attempt to install high Sierra through a bootable usb I created with terminal using
sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled

 

[Mr_Brightside_@]

When did you download the High Sierra installer?

Try all these combos:

Command (⌘)-R
Reinstall the latest macOS that was installed on your Mac (recommended).

Option-⌘-R
Upgrade to the latest macOS that is compatible with your Mac.

Shift-Option-⌘-R
Reinstall the macOS that came with your Mac, or the closest version still available.

 

[Oonagh oh]

When did you download the High Sierra installer?

Try all these combos:

Command (⌘)-R
Reinstall the latest macOS that was installed on your Mac (recommended).

Option-⌘-R
Upgrade to the latest macOS that is compatible with your Mac.

Shift-Option-⌘-R
Reinstall the macOS that came with your Mac, or the closest version still available.

all sorted! managed to download the os that came with my Mac, which was high Sierra!!! Thank you for the help

 

[alcpf]

all sorted! managed to download the os that came with my Mac, which was high Sierra!!! Thank you for the help

Hi. I have the same problem. What did you for fix the problem?

 

[Minghold]

Do you have access to another machine with High Sierra on it?
Do you have either Carbon Copy Cloner or Get Backup Pro?
Do you have an external-drive with empty space equal to the used space of your internal drive?