Error: Cannot install in Homebrew on ARM processor in Intel default prefix (/usr/local)

For what it's worth, before installing Homebrew you will need to install Rosetta2 emulator for the new ARM silicon (M1 chip). I just installed Rosetta2 via terminal using:

/usr/sbin/softwareupdate --install-rosetta --agree-to-license

This will install rosetta2 with no extra button clicks.

After installing Rosetta2 above you can then use the Homebrew cmd and install Homebrew for ARM M1 chip: arch -x86_64 /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install.sh)"

Once Homebrew for M1 ARM is installed use this Homebrew command to install packages: arch -x86_64 brew install <package>

Homebrew needs to be installed in two places on Apple silicon: in /usr/local for rosetta-emulated (Intel) code, and /opt/homebrew for ARM64. These are somewhat hard-coded and the /opt/homebrew one MUST be used for ARM code, as it stands today, and is non-negotiable. However, it's easy enough to install and you can follow the general instructions on the official docs. You open a Rosetta shell first.

% arch -x86_64 zsh
% cd /usr/local && mkdir homebrew
% curl -L https://github.com/Homebrew/brew/tarball/master | tar xz --strip 1 -C homebrew

Later, to install tools under intel you can use the arch command per-command or open a zsh terminal as above.

arch -x86_64 /usr/local/homebrew/bin/brew install sometool

For the ARM architecture, you don't need to use arch but you do need to use the full path of the homebrew command.

/opt/homebrew/bin/brew install sometool

You could rename the brew commands to something like brew86 and brewARM to help keep them separate.

Just use:

arch -arm64 brew install package-name

replace 'package-name' with the package you want to install.

Did a temporary fix by enabling Open using Rosetta option in the terminal app from Utilities folder.

However, it would be great to know the actual solution for this question to use the native way.

Run this in the terminal it fixes the issue

eval "$(/opt/homebrew/bin/brew shellenv)"

This issue with new macbook pro M1 chip

Error: Cannot install in Homebrew on ARM processor in Intel default prefix (/usr/local)!

For Resolve follow below steps

Step1

$ brew bundle dump

Step2

$ /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

Step3 Edit file below

$ vi ~/.bashrc or vi ~/.zshrc

Edit below line in above file

export PATH=/opt/homebrew/bin:$PATH

There is a lot of helpful info in the replies here, but there doesn't seem to be a direct answer to the original request, "Need help with exact steps to follow."

In case it may help people facing this issue in the future, I'll share the exact steps that I followed to resolve the issue.

The following CLI commands are intended to be run on an Apple silicon-equipped Mac in the built-in Terminal application running the macOS-default shell, Zsh:

1. Run a Homebrew command to confirm that an error like the following appears:

   $ brew install <formula>
   

   Error: Cannot install in Homebrew on ARM processor in Intel default prefix (/usr/local)!
   Please create a new installation in /opt/homebrew using one of the
   "Alternative Installs" from:
     https://docs.brew.sh/Installation
   

   Or:

   $ brew doctor
   

   Warning: Your Homebrew's prefix is not /opt/homebrew.
   Some of Homebrew's bottles (binary packages) can only be used with the default
   prefix (/opt/homebrew).
   You will encounter build failures with some formulae.
   

   If either of these errors appears, it is likely that the steps below are applicable to your case.

2. Navigate to the /opt folder:

   $ cd /opt
   

3. Create a folder named homebrew. By default superuser privileges are required to write inside of the /opt folder, which means that it is necessary to use sudo:

   $ sudo mkdir homebrew
   

4. Grant write access to the homebrew folder so that your user can perform the Homebrew installation:

   $ sudo chmod go+w homebrew
   

5. Perform the four steps listed on the "Alternative Installs" page (the page mentioned in the first error message in step 1):

   1. Install Homebrew:

      $ curl -L https://github.com/Homebrew/brew/tarball/master | tar xz --strip 1 -C homebrew
      

   2. Set Homebrew's prefix in your current Terminal session:

      $ eval "$(homebrew/bin/brew shellenv)"
      

   3. Update Homebrew:

      $ brew update --force --quiet
      

   4. Revoke write access to specific folders and files:

      $ chmod -R go-w "$(brew --prefix)/share/zsh"
      

6. Set Homebrew's prefix in future Terminal sessions by adding the necessary command to one of Zsh's startup files. As far as I can tell, .zshrc is the preferred startup file for this type of command:

   $ echo 'eval "$(/opt/homebrew/bin/brew shellenv)"' >> ~/.zshrc
   

   Note that if there are any other existing Terminal sessions on your machine that have been open since before running the above command, the correct Homebrew prefix will still be unset in those sessions.

7. Confirm that Homebrew's prefix is now properly set:

   $ type -a brew
   

   brew is /opt/homebrew/bin/brew
   brew is /usr/local/bin/brew
   

   Or:

   $ brew doctor
   

   Your system is ready to brew.
   

It should now be possible to continue using Homebrew normally.

Homebrew is now available for the new apple M1 chip at https://docs.brew.sh/Installation. The script installs in a new location, ‘/opt/homebrew’ instead of ‘/usr/local’ which requires that you implement a couple lines of script after the install, substituting your username. You can copy/paste from the comments in your install. Just don’t skip these steps.

==> Next steps:
- Add Homebrew to your PATH in /Users/[username]/.zprofile:
    echo 'eval "$(/opt/homebrew/bin/brew [username])"' >> /Users/[username]/.zprofile
    eval "$(/opt/homebrew/bin/brew [username])"

Note: This works for a clean install of Homebrew on a new machine. If you have already installed an old version of Homebrew and got it working, I believe you need to uninstall that first -or- you may find this a quicker work-around http://blog.wafrat.com/homebrew-on-mac-with-m1/. Not tested.

This also may occur if you are trying to run your command in IntelliJ Terminal. Just try to run in (Regular) Terminal.

First run this command:

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

then it will ask you a question, hit return, then wait for the installation to be completed. After than run this command:

brew bundle dump

Go over to https://brew.sh and use the command. It will download and install brew again correctly.

I had installed Homebrew using iTerm enabled for the Apple ARM chip (M1), but when using a different terminal program that was Intel-based (and thus opening in Rosetta) I got this error. The latter app is seen as Intel, and thus wants to use the older Homebrew path.

See: https://docs.brew.sh/Installation

1. Clone homebrew

$ cd /opt
$ sudo git clone https://github.com/Homebrew/brew homebrew

2. Chown dir

$ sudo chown -R $(whoami):staff /opt/homebrew

3. Update new brew shellenv temporarily, more shellenv meaning see man brew

$ eval "$(homebrew/bin/brew shellenv)"

4. New brew update

$ brew update --force --quiet
==> Homebrew has enabled anonymous aggregate formula and cask analytics.
Read the analytics documentation (and how to opt-out) here:
  https://docs.brew.sh/Analytics
No analytics have been recorded yet (nor will be during this `brew` run).

==> Tapping homebrew/core
Cloning into '/opt/homebrew/Library/Taps/homebrew/homebrew-core'...
remote: Enumerating objects: 1265097, done.
remote: Counting objects: 100% (207/207), done.
remote: Compressing objects: 100% (97/97), done.
remote: Total 1265097 (delta 120), reused 192 (delta 110), pack-reused 1264890
Receiving objects: 100% (1265097/1265097), 517.64 MiB | 3.02 MiB/s, done.
Resolving deltas: 100% (872476/872476), done.
Tapped 3 commands and 6273 formulae (6,616 files, 566.4MB).

5. Make sure remove other person write privage

$ chmod -R go-w "$(brew --prefix)/share/zsh"

6. Confirm new brew version

$ brew --version
Homebrew 3.6.0
Homebrew/homebrew-core (git revision 57f5c02ec6a; last commit 2022-09-10)

7. Brew config show

/opt/homebrew on  stable (93ea8cb2c)  17:17:54
$ brew config
HOMEBREW_VERSION: 3.6.0
ORIGIN: https://github.com/Homebrew/brew
HEAD: 93ea8cb2c40e1ef25f1489b0267526bd47bc8030
Last commit: 3 days ago
Core tap ORIGIN: https://github.com/Homebrew/homebrew-core
Core tap HEAD: 57f5c02ec6af877482ecd8753066d6a277cd3213
Core tap last commit: 72 minutes ago
Core tap branch: master
HOMEBREW_PREFIX: /opt/homebrew
HOMEBREW_REPOSITORY: /opt/homebrew
HOMEBREW_CELLAR: /opt/homebrew/Cellar
HOMEBREW_CASK_OPTS: []
HOMEBREW_MAKE_JOBS: 10
Homebrew Ruby: 2.6.8 => /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/ruby
CPU: 10-core 64-bit westmere
Clang: 13.1.6 build 1316
Git: 2.32.1 => /Applications/Xcode.app/Contents/Developer/usr/bin/git
Curl: 7.79.1 => /usr/bin/curl
macOS: 12.5.1-x86_64
CLT: 13.4.0.0.1.1651278267
Xcode: 13.4.1
Rosetta 2: true

8. Add new brew shellenv to strart bash shell, eg. ~/.zshrc、~/.barshrc etc.

eval "$(/opt/homebrew/bin/brew shellenv)"

Run this command as this will resolve the issue

arch -arm64 brew install kotlin

So I bought a new M1 and migrated to it. I took it back and migrated back. I was receiving this error. Found that I needed to run sudo rm -Rf /opt/homebrew after re-installing brew to get things flowing again. 16G Ram on the M1 didn't replace my workflow with Intel using 64G.

Try brew upgrade then re-run your command.