Quick answer

Mount the EFI partition, open EFI/OC/config.plist in a plist editor such as ProperTree, make a backup copy first, then save, unmount and restart. ESP Mounter mounts the EFI partition for you and detects OpenCore automatically.

OpenCore keeps almost all of its settings in a single file, config.plist, inside the EFI partition at EFI/OC/config.plist. To change a setting, add a kext or update a quirk, you first have to mount that partition, then edit the file with care. A single typo can stop the Mac from booting, so the steps below include a backup.

Steps

How to
  1. Mount the EFI partition. Use Terminal or ESP Mounter. ESP Mounter detects OpenCore and Clover installs and shows which disk you booted from, so you can pick the right EFI partition quickly.
  2. Back up first. Copy the whole EFI folder to your desktop, or at least duplicate config.plist as config-backup.plist.
  3. Open the file. Open EFI/OC/config.plist in a plist editor such as ProperTree. Avoid editing the raw XML in a text editor.
  4. Make one change at a time. Small edits are easy to undo when something goes wrong.
  5. Validate it. Run the ocvalidate utility that ships with your OpenCore release against the file to catch common mistakes.
  6. Save, unmount and restart. Unmount the EFI partition, restart, and check that the Mac boots normally.

If something goes wrong

Boot from another disk, a USB installer or the OpenCore picker on a different drive, mount the EFI partition again and put the backup back. If you maintain a Mac with OpenCore Legacy Patcher, see our OCLP guide, and for ready-made EFI folders see the EFI Repository.

When you copy an EFI folder from one disk to another, ESP Mounter keeps an automatic backup of anything it overwrites, which is a handy safety net.

Frequently asked questions

Where is config.plist in an OpenCore install?
Inside the EFI partition at EFI/OC/config.plist. Clover keeps its file at EFI/CLOVER/config.plist.
What should I edit config.plist with?
A plist editor made for OpenCore, such as ProperTree, is the usual choice. Xcode or any other plist editor can open it too, but a text editor makes it easy to break the XML.
How do I check my edits before restarting?
OpenCore releases include a utility called ocvalidate in the Utilities folder. Run it on your config.plist to catch common mistakes before you reboot.
What if the Mac will not boot after my change?
Boot from another disk or a USB installer, mount the EFI partition again and put your backup config.plist back.