NPM permission error while installing

Question

i am trying to install yeoman on my server but for some reason do i keep getting a permission denied error.

$npm install -g yo
/root/.node/bin/yo -> /root/.node/lib/node_modules/yo/cli.js

> [email protected] postinstall /root/.node/lib/node_modules/yo
> yodoctor

sh: 1: yodoctor: Permission denied

npm ERR! [email protected] postinstall: `yodoctor`
npm ERR! Exit status 127
npm ERR! 
npm ERR! Failed at the [email protected] postinstall script.
npm ERR! This is most likely a problem with the yo package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR!     yodoctor
npm ERR! You can get their info via:
npm ERR!     npm owner ls yo
npm ERR! There is likely additional logging output above.
npm ERR! System Linux 3.13.0-37-generic
npm ERR! command "/usr/bin/node" "/usr/bin/npm" "install" "-g" "yo"
npm ERR! cwd /root
npm ERR! node -v v0.10.33
npm ERR! npm -v 1.4.28
npm ERR! code ELIFECYCLE
npm ERR! not ok code 0

i have tried to reinstall ubuntu (14.04) but nothing works.

Answer 1

I think Shantaru is right, you need to do it with sudo.

Try this

sudo npm uninstall -g yo
sudo npm cache clean
sudo npm install -g yo

I have a similar problem weeks ago and that works.

Edit: If that didn't work, do this before:

npm config set unsafe-perm true