NPM err! please try running this command again as root/Administrator

Sometimes when you try to install npm package globally, eg:

npm install express -g

You can get an error like below:

Error: EACCES, mkdir '/usr/local/lib/node_modules/express'
npm ERR! { [Error: EACCES, mkdir '/usr/local/lib/node_modules/express']
npm ERR! errno: 3,
npm ERR! code: 'EACCES',
npm ERR! path: '/usr/local/lib/node_modules/express',
npm ERR! fstream_type: 'Directory',
npm ERR! fstream_path: '/usr/local/lib/node_modules/express',
npm ERR! fstream_class: 'DirWriter',
npm ERR! fstream_stack:
npm ERR! [ '/usr/local/lib/node_modules/npm/node_modules/fstream/lib/dir-writer.js:36:23',
npm ERR! '/usr/local/lib/node_modules/npm/node_modules/mkdirp/index.js:37:53',
npm ERR! 'Object.oncomplete (fs.js:107:15)' ] }
npm ERR!
npm ERR! Please try running this command again as root/Administrator.


Nasty error occurs not only during installing express via npm package manager, but matter of fact, during installing other node packages too.

Error suggests solution.

NPM err! please try running this command again as root/Administrator

You are most likely to get that error if using Mac OS or linux. Main reason is that npm (Node Package Manager) requires “sudo” (root/Administrator) privileges. Running it as a regular user you don’t really have a write access to listed directory /usr/local/lib/node_modules therefore new express directory can not be created at that location.

There is more than one method to go about this.

Method 1: sudo

You can simply sudo yourself and run below command

sudo npm install express -g

Disadvantage is that you will have to sudo yourself every time you want to install package with “-g” (global) option

Method 2: Group privileges

You can add yourself to the group that npm user belongs to. Check the group running:

ls -al /usr/local/bin/npm

Add yourself to the group by running

usermod -a -G your_user_name desired_group_name

Big disadvantage of that method is that it will give you access to everything that "desired group" has access to.

Method 3: make npm a sudoer

You might be better off by granting access to npm more permanently without the need of typing a password every time you run sudo npm.

To do that can modify /etc/sudoers file. Entry we are about to add should follow its general syntax:

user_name  host_name=command_location

And so before you proceed login as root

sudo su

And then execute below command replacing “yourusername” with your user name

echo "your_user_name  localhost=/usr/local/bin/npm" >> /etc/sudoers

Now CTRL-D to logout from root and CTRL-D one more time logout from your account. Reopen terminal and try to install your express (or any other node package) with

sudo npm install -g package_name

Disadvantage of that method is npm has been granted sudo permissions. It is not a problem if it is just you on the server, or mac but musn't be used if there is more users.

Method 4: make npm a sudoer

…and voilà! There you have it.

Published by IndieForger