This looks like a permissions issue in your home directory. To reclaim ownership of the .npm directory execute

sudo chown -R $(whoami) ~/.npm

Also you will need the write permission in node_modules directory:

sudo chown -R $USER /usr/local/lib/node_modules

Solution 1: Consider permissions during node installation

(Don't hack with permissions, install node the right way)

Permissions you used when installing node will be required when doing things like writing in your npm directory (npm link, npm install -g, etc.).

You probably ran node installation with root permissions, that's why the global package installation is asking you to be root.

There is two ways to manage your node installation:

• On a development machine: Install node with NVM (Node Version Manager).
• On a production machine: Install node directly with appropriate permissions.

NVM

On a development machine, you should not install and run node with root permissions, otherwise things like npm link, npm install -g will need the same permissions.

NVM allow you to install node without root permissions and also allow you to install many versions of node to play easily with them.. Perfect for development.

1. Start uninstalling node (root permission will probably be required)
2. Then install NVM following instructions on this page.
3. Install node the proper way: nvm install stable

Now npm link, npm install -g will not require you to be root anymore :D

Directly

On a production machine, you can do everything with root permissions. Node installation, packages installations, etc.

Run npm link, npm install -g, etc. with root permissions.

Solution 2: Install packages globally for a given user

If you are on OSX or Linux, you can create a user dedicated directory for your global package and setup npm and node to know how to find globally installed packages.

Check out this great article for step by step instructions on installing npm modules globally without sudo.

I encountered this when installing Recess (https://github.com/twitter/recess) to compile my CSS for Bootstrap 3.

When installing recess:

-npm install recess -g

1. You need to unlock permissions in your home directory, like Noah says:

   sudo chown -R `whoami` ~/.npm
   

2. You also need write permissions to the node_modules directory, like Xilo says, so if it still isn't working, try:

   sudo chown -R `whoami` /usr/local/lib/node_modules
   

3. If you are still seeing errors, you may also need to correct /usr/local permissions:

   sudo chown -R `whoami` /usr/local
   

Please note that as indicated in this post /usr/local/ isn't actually a system dir if you are on a Mac, so, this answer is actually perfectly "safe" for Mac users. However, if you are on Linux, see Christopher Will's answer below for a multi-user friendly, system dir safe (but more complex) solution.

Other answers suggest changing the ownership or permissions of system directories to a specific user. Here is a a more generic and safer approach that supports multiuser.

It's safer to create a new group for node-users and add the required users to this group, further to set the ownership of node-dependant files/directories to this group.

# Create new group
sudo groupadd nodegrp 

# Add user to group (logname is a variable and gets replaced by the currently logged in user)
sudo usermod -a -G nodegrp `logname`

# Instant access to group without re-login
newgrp nodegrp

# Check group - nodegrp should be listed as well now
groups

# Change group of node_modules, node, npm to new group 
sudo chgrp -R nodegrp /usr/lib/node_modules/
sudo chgrp nodegrp /usr/bin/node
sudo chgrp nodegrp /usr/bin/npm

# (You may want to change a couple of more files (like grunt etc) in your /usr/bin/ directory.)

Now you can easily install your modules as user

npm install -g generator-angular

Some modules (grunt, bower, yo etc.) will still need to be installed as root. This is because they create symlinks in /user/bin/.

Changing the owner on "system-global" folders is a hack. On a fresh install, I would configure NPM to use an already writable location for "user-global" programs:

npm config set prefix ~/npm

Then make sure you add that folder to your path:

export PATH="$PATH:$HOME/npm/bin"

See @ErikAndreas' answer to NPM modules won't install globally without sudo .

As if we need more answers here, but anyway..

Sindre Sorus has a guide Install npm packages globally without sudo on OS X and Linux outlining how to cleanly install without messing with permissions:

Here is a way to install packages globally for a given user.

1. Create a directory for your global packages

   mkdir "${HOME}/.npm-packages"
   

2. Reference this directory for future usage in your .bashrc/.zshrc:

   NPM_PACKAGES="${HOME}/.npm-packages"
   

3. Indicate to npm where to store your globally installed package. In your $HOME/.npmrc file add:

   prefix=${HOME}/.npm-packages
   

4. Ensure node will find them. Add the following to your .bashrc/.zshrc:

   NODE_PATH="$NPM_PACKAGES/lib/node_modules:$NODE_PATH"
   

5. Ensure you'll find installed binaries and man pages. Add the following to your .bashrc/.zshrc:

   PATH="$NPM_PACKAGES/bin:$PATH"
   # Unset manpath so we can inherit from /etc/manpath via the `manpath`
   # command
   unset MANPATH # delete if you already modified MANPATH elsewhere in your config
   MANPATH="$NPM_PACKAGES/share/man:$(manpath)"
   

Check out npm-g_nosudo for doing the above steps automagically

Checkout the source of this guide for the latest updates.

When you run npm install -g somepackage, you may get an EACCES error asking you to run the command again as root/Administrator. It's a permissions issue.

It's easy to fix, open your terminal (Applications > Utilities > Terminal)

sudo chown -R $USER /usr/local/lib/node_modules

** I strongly recommend you to not use the package management with sudo (sudo npm -g install something), because you can get some issues later **

Reference: http://foohack.com/2010/08/intro-to-npm/

In my case,it's because of the permission of ~/tmp.So I do:

sudo chown -R $USER ~/tmp

And it's OK!

For me, execute only

sudo chown -R $(whoami) ~/.npm

doesn't work. Then, I execute too

sudo chown -R $(whoami) /usr/lib/node_modules/
sudo chown -R $(whoami) /usr/bin/node
sudo chown -R $(whoami) /usr/bin/npm

And all works fine!

For Mac (adopted from Christoper Will's answer)

Mac OS X 10.9.4

1. System Preference > Users & Groups > (unlock) > press + :

   New Account > "Group"
   Account Name : nodegrp

   After creating the group, tick the user to be included in this group

2. sudo chgrp -R nodegrp /usr/local/lib/node_modules/
   sudo chgrp nodegrp /usr/bin/node
   sudo chgrp nodegrp /usr/bin/npm
   sudo chown -R $(whoami):nodegrp ~/.npm

I had a similar problem at NPM modules won't install globally without sudo, the issue was that when i installed node i did it with sudo via chris/lea ppa repo.

My solution was to uninstall node and then install it this way:

Download latest stable node sources from nodejs.org #in my case node-v0.10.20.tar.gz

tar -zxf node-v0.10.20.tar.gz #uncompress sources

cd node-v0.10.20 #enter uncompressed folder

sudo chown $USER -R /usr/local

./configure --prefix=/usr/local && make && make install

PD: If you don't want to change ownership of the /usr/local folder, you can install it somewhere you already own. The problem of this approach is that you will have to bind the installation folder with the bash command line so that we can use the node command later on

mkdir ~/opt

./configure --prefix=~/opt && make && make install

echo 'export PATH=~/opt/bin:${PATH}' >> ~/.bashrc #or ~/.profile or ~/.bash_profile or ~/.zshenv depending on the current Operative System

With either of those approaches, you will be able to do the following without using sudo

npm install -g module_to_install

On Mac OS X, when installing with Homebrew's brew install npm, the installation path is /usr/local/share/npm/ with both bin/ and lib/node_modules/ subfolders.

Running this command to change to owner to your currently logged in user should fix it all up, and allow you to install global NPM packages without sudo.

sudo chown -R $USER ~/.npm /usr/local/share/npm/

osx homebrew

Actually, I was also having the same problem. I was running Ubuntu. Mine problem arises because I'd lost my public key of the Ubuntu. Even updating my system was not happening. It was giving GPG error. In that case, you can regain your key by using this command:

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys <key in GPG error>

After that npm works fine!

All the above is not necessary.

The issue I was having was I was using the -g when I was running NPM. I couldn't work out how I wasn't getting a 'npm_module' folder created in my project.

The solution is to run 'NPM init' This creates a 'package.json' and the 'npm_module' folder where all subsequent modules will be loaded into. When running npm DO NOT use -g use -s to update your 'package.json' file.

Here is a good video explaining

I found that if you only sudo -s "it just starts up a shell with root permissions as a one step" and it really works for me. I don't know if it's a good practice or not.

I hope it helps.

Reference: http://apple.stackexchange.com/posts/14423/revisions

John Papa points to the history and reasoning behind this issue and gives a solid fix:

John Papa's steps are to:

1. Use brew to install node without npm
2. Update your .bash_profile/.bashrc to let npm and node know where to install and find packages
3. Use brew to update node and npm to update itself

Hope this helps the curious!

This is the solution I utilized and worked. I tried utilizing whoami never worked.

sudo chown -R $USER /usr/local/lib/node_modules

then

sudo chown -R $USER /usr/local/bin/npm

then

sudo chown -R $USER /usr/local/bin/node

If changing permissions for directory /usr/local/lib/npm_modules not helps, u should add your user to group (in most cases this is staff group), that has rwx rights for /usr/bin directory. Because npm tries to make symlink with /usr/bin/__package__.

P.S. Don't forget to relogin after changing user group

I set my user account as the owner of the /usr/local directory, so that can just issue normal commands in there.

sudo chown -R $USER /usr/local

Reference: http://howtonode.org/introduction-to-npm

sudo chown -R `whoami` /usr/local/lib