Tried to do a complete fresh install of Sierra. "Permission Denied" when I go to Install

Solution 1:

This one should help it

https://discussions.apple.com/thread/7860429

Needed to erase and rename the Drive to Macintosh HD

Solution 2:

If you updated your OS to High Sierra and you want to downgrade to Sierra, make sure the partition format is Mac OS Extended not AFPS. Mine was AFPS and that's what caused the error.

Solution 3:

Only do this if you have a backup and are allowed to delete everything on the internal drive

If you have access to another mac computer, you can download the app to install mojave (or whatever the right version you want is), and then use this guide to create a bootable usb drive:

Official Apple Guide

Once you have created the installation media, boot into macOS while holding Option. An icon will come up that says install macOS and then go to disk utility. Erase the disk and reformat it to APFS. If this doesn't work, go to the terminal and use diskutil list to find the right disk, and diskutil eraseDisk APFS macOS disk3. Make sure to replace the disk3 with the correct disk identifier that you got with diskutil list.

After you have prepared your internal disk, go back to install it, and it should work.

The reason this works I think is because the installation is not booting off of the internal drive, but in internet recovery it is booting off the internal drive.