title: npm install causes errors like npm ERR! tar.unpack untar error on Debian
body: <p>Installing Grunt as in the <a href="http://getbootstrap.com/getting-started/#grunt-installing" rel="noreferrer">Bootstrap documentation</a> shown, I first installed <code>grunt-cli</code> globally with <code>npm install -g grunt-cli</code> and now I'm trying to execute <code>npm install</code>, but only getting errors:</p>
  
  <pre><code>root@devvm:/var/www/axit/portfolio/public/bower_components/bootstrap# npm install
  npm ERR! tar.unpack untar error /root/.npm/wrappy/1.0.1/package.tgz
  npm ERR! tar.unpack untar error /root/.npm/wrappy/1.0.1/package.tgz
  npm ERR! tar.unpack untar error /root/.npm/brace-expansion/1.1.0/package.tgz
  npm ERR! tar.unpack untar error /root/.npm/delayed-stream/0.0.5/package.tgz
  npm WARN optional dep failed, continuing form-data@0.1.4
  npm ERR! tar.unpack untar error /root/.npm/is-property/1.0.2/package.tgz
  npm WARN optional dep failed, continuing request@2.54.0
  npm ERR! Linux 3.2.0-4-amd64
  npm ERR! argv "node" "/usr/local/bin/npm" "install"
  npm ERR! node v0.10.35
  npm ERR! npm  v2.7.4
  npm ERR! path /var/www/axit/portfolio/public/bower_components/bootstrap/node_modules/grunt-saucelabs/node_modules/sauce-tunnel/node_modules/request/node_modules/form-data/node_modules/combined-stream/node_modules/delayed-stream/test/integration/test-delayed-http-upload.js
  npm ERR! code EPERM
  npm ERR! errno 50
  
  npm ERR! Error: EPERM, open '/var/www/axit/portfolio/public/bower_components/bootstrap/node_modules/grunt-saucelabs/node_modules/sauce-tunnel/node_modules/request/node_modules/form-data/node_modules/combined-stream/node_modules/delayed-stream/test/integration/test-delayed-http-upload.js'
  npm ERR!  { [Error: EPERM, open '/var/www/axit/portfolio/public/bower_components/bootstrap/node_modules/grunt-saucelabs/node_modules/sauce-tunnel/node_modules/request/node_modules/form-data/node_modules/combined-stream/node_modules/delayed-stream/test/integration/test-delayed-http-upload.js']
  npm ERR!   errno: 50,
  npm ERR!   code: 'EPERM',
  npm ERR!   path: '/var/www/axit/portfolio/public/bower_components/bootstrap/node_modules/grunt-saucelabs/node_modules/sauce-tunnel/node_modules/request/node_modules/form-data/node_modules/combined-stream/node_modules/delayed-stream/test/integration/test-delayed-http-upload.js' }
  npm ERR! 
  npm ERR! Please try running this command again as root/Administrator.
  npm ERR! Linux 3.2.0-4-amd64
  npm ERR! argv "node" "/usr/local/bin/npm" "install"
  npm ERR! node v0.10.35
  npm ERR! npm  v2.7.4
  npm ERR! path npm-debug.log.ba707f2a7a688e388708bbe88e2dd4ed
  npm ERR! code ETXTBSY
  npm ERR! errno 62
  
  npm ERR! ETXTBSY, rename 'npm-debug.log.ba707f2a7a688e388708bbe88e2dd4ed'
  npm ERR! 
  npm ERR! If you need help, you may report this error at:
  npm ERR!     &lt;https://github.com/npm/npm/issues&gt;
  
  npm ERR! Please include the following file with any support request:
  npm ERR!     /var/www/axit/portfolio/public/bower_components/bootstrap/npm-debug.log
  </code></pre>
  
  <p>I've just copied the project in a non-shared folder and started <code>npm install</code> again. And it worked. So, it seems to be a shared folder issue. But what exactly? <a href="http://www.ahtik.com/blog/fixing-your-virtualbox-shared-folder-symlink-error/" rel="noreferrer">Symlinks are enabled</a> for this shared folder and I started the VM as admin (it helped, when I had similar issues installing Bower).</p>
  
  <p>What is causing these errors and how to solve this problem?</p>
  
  <blockquote>
    <p>Environment: VirtualBox with Debian guest system and Windows 7 host system.</p>
  </blockquote>
  
  <p><strong>EDIT</strong></p>
  
  <p>Now (I think after I've successfully executed <code>npm install</code> in a non-shared folder) I'm geting different errors:</p>
  
  <p>When I start the VM in the common way:</p>
  
  <pre><code>root@devvm:/var/www/axit/portfolio/public/bower_components/bootstrap# npm install
  npm ERR! tar.unpack untar error /root/.npm/delayed-stream/0.0.5/package.tgz
  npm WARN optional dep failed, continuing form-data@0.1.4
  npm ERR! tar.unpack untar error /root/.npm/wrappy/1.0.1/package.tgz
  npm ERR! tar.unpack untar error /root/.npm/wrappy/1.0.1/package.tgz
  npm ERR! tar.unpack untar error /root/.npm/brace-expansion/1.1.0/package.tgz
  npm ERR! Linux 3.2.0-4-amd64
  npm ERR! argv "node" "/usr/local/bin/npm" "install"
  npm ERR! node v0.10.35
  npm ERR! npm  v2.7.4
  npm ERR! path ../semver/bin/semver
  npm ERR! code UNKNOWN
  npm ERR! errno -1
  
  npm ERR! UNKNOWN, symlink '../semver/bin/semver'
  npm ERR! 
  npm ERR! If you need help, you may report this error at:
  npm ERR!     &lt;https://github.com/npm/npm/issues&gt;
  npm ERR! Linux 3.2.0-4-amd64
  npm ERR! argv "node" "/usr/local/bin/npm" "install"
  npm ERR! node v0.10.35
  npm ERR! npm  v2.7.4
  npm ERR! path npm-debug.log.428531818e2d916d5ae79bdf94dd73b3
  npm ERR! code ETXTBSY
  npm ERR! errno 62
  
  npm ERR! ETXTBSY, rename 'npm-debug.log.428531818e2d916d5ae79bdf94dd73b3'
  npm ERR! 
  npm ERR! If you need help, you may report this error at:
  npm ERR!     &lt;https://github.com/npm/npm/issues&gt;
  
  npm ERR! Please include the following file with any support request:
  npm ERR!     /var/www/axit/portfolio/public/bower_components/bootstrap/npm-debug.log
  </code></pre>
  
  <p>When I start the VM as <code>Administrator</code>:</p>
  
  <pre><code>root@devvm:/var/www/axit/portfolio/public/bower_components/bootstrap# npm install
  npm ERR! tar.unpack untar error /root/.npm/wrappy/1.0.1/package.tgz
  npm ERR! tar.unpack untar error /root/.npm/wrappy/1.0.1/package.tgz
  npm ERR! tar.unpack untar error /root/.npm/delayed-stream/0.0.5/package.tgz
  npm ERR! tar.unpack untar error /root/.npm/brace-expansion/1.1.0/package.tgz
  npm WARN optional dep failed, continuing form-data@0.1.4
  npm ERR! Linux 3.2.0-4-amd64
  npm ERR! argv "node" "/usr/local/bin/npm" "install"
  npm ERR! node v0.10.35
  npm ERR! npm  v2.7.4
  npm ERR! path /var/www/axit/portfolio/public/bower_components/bootstrap/node_modules/grunt-contrib-qunit/node_modules/grunt-lib-phantomjs/node_modules/phantomjs/node_modules/fs-extra/node_modules/rimraf/node_modules/glob/node_modules/once/node_modules/wrappy
  npm ERR! code UNKNOWN
  npm ERR! errno -1
  
  npm ERR! UNKNOWN, mkdir '/var/www/axit/portfolio/public/bower_components/bootstrap/node_modules/grunt-contrib-qunit/node_modules/grunt-lib-phantomjs/node_modules/phantomjs/node_modules/fs-extra/node_modules/rimraf/node_modules/glob/node_modules/once/node_modules/wrappy'
  npm ERR! 
  npm ERR! If you need help, you may report this error at:
  npm ERR!     &lt;https://github.com/npm/npm/issues&gt;
  npm ERR! Linux 3.2.0-4-amd64
  npm ERR! argv "node" "/usr/local/bin/npm" "install"
  npm ERR! node v0.10.35
  npm ERR! npm  v2.7.4
  npm ERR! path npm-debug.log.0bb66467f3aae813a34e03a797f8da19
  npm ERR! code ETXTBSY
  npm ERR! errno 62
  
  npm ERR! ETXTBSY, rename 'npm-debug.log.0bb66467f3aae813a34e03a797f8da19'
  npm ERR! 
  npm ERR! If you need help, you may report this error at:
  npm ERR!     &lt;https://github.com/npm/npm/issues&gt;
  
  npm ERR! Please include the following file with any support request:
  npm ERR!     /var/www/axit/portfolio/public/bower_components/bootstrap/npm-debug.log
  </code></pre>