[Solved] Downgrade from Mojave to High Sierra

[supergen]

THANK YOU!

 

[carlgruf]

To downgrade to High Sierra without erasing your drive is quite easy as long as you are using APFS.

1. If you have converted your drive to APFS, simply create a new volume in the same container as your boot drive. Do not set any size restrictions on that new volume.
2. Install High Sierra on that new volume according to this thread.
3. Boot it up and copy the files you need from the old volume to the new volume. The nice thing with the APFS file system is that the volumes dynamically share the same free space within the container. When finished simply delete the old drive.

I just did that and managed to downgrade to High Sierra without erasing anything. You of course need some free space on your old drive so that you have some space to work with.

 

[SkinlessJSn]

Can I just run the HS installer from Mojave with the new container as the target?

**EDIT: Nope. Mojave gets weirded out by it being older.

To downgrade to High Sierra without erasing your drive is quite easy as long as you are using APFS.

1. If you have converted your drive to APFS, simply create a new volume in the same container as your boot drive. Do not set any size restrictions on that new volume.
2. Install High Sierra on that new volume according to this thread.
3. Boot it up and copy the files you need from the old volume to the new volume. The nice thing with the APFS file system is that the volumes dynamically share the same free space within the container. When finished simply delete the old drive.

I just did that and managed to downgrade to High Sierra without erasing anything. You of course need some free space on your old drive so that you have some space to work with.

 

[carlgruf]

Can I just run the HS installer from Mojave with the new container as the target?

**EDIT: Nope. Mojave gets weirded out by it being older.

The new volume should be the target, in the same container as your old boot volume.
In APFS you have volumes inside containers. You only need one container on your disk. But you should create a new volume inside the container, beside your old volume. In the new volume you install HS.
Dont mix the two things up, containers and volumes.
The advantage of working with volumes is that they dynamically share the free space of the container. And they show up like ”harddrives” on your desktop. No need any longer for the old partitioning nightmare.
Hope it works out for you!

 

[Iraija]

I've formatted my hard drive several times now, but the same message keeps appearing in my installer. Any other possible solutions?
Thanks!

 

[jessicasoba]

error when trying boot on HS installer Error loading kernel cache (0xe), how?