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su - setup.admin
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Updating Homebrew may result in error if you do it in between Mac OS X updates,
brew update Error: The /usr/local directory is not writable. Even if this directory was writable when you installed Homebrew, other software may change permissions on this directory. For example, upgrading to OS X El Capitan has been known to do this. Some versions of the "InstantOn" component of Airfoil or running Cocktail cleanup/optimizations are known to do this as well. You should probably change the ownership and permissions of /usr/local back to your user account. sudo chown -R setup.admin:admin /usr/local/
In this in case using the chown is no longer possible with Mac OS X "High Sierra" 10.13.4 and you will receive the following error,
sudo chown -R setup.admin:admin /usr/local/ chown: /usr/local: Operation not permitted
Instead just uninstall,
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Ignore the note about the folders to delete. I my example remotdesktop was generated by another program. No idea why Homebrew would tell you to delete folder other program's create.