npm install opens a lot of connections and hangs

npm-debug-1.log

npm info it worked if it ends with ok
npm verb cli [ 'C:\\Program Files\\nodejs\\node.exe',
npm verb cli   'C:\\Program Files\\nodejs\\node_modules\\npm\\bin\\npm-cli.js',
npm verb cli   'install',
npm verb cli   'grunt-contrib-uglify',
npm verb cli   '-g',
npm verb cli   '-ddd' ]
npm info using npm@3.3.6
npm info using node@v5.0.0
[...]
npm sill mapToRegistry name parse-json
npm sill mapToRegistry using default registry
npm sill mapToRegistry registry https://registry.npmjs.org/
npm sill mapToRegistry uri https://registry.npmjs.org/parse-json
npm verb addNameRange registry:https://registry.npmjs.org/parse-json not in flight; fetching
npm sill cache afterAdd strip-bom@2.0.0
npm verb afterAdd C:\Users\Joram\AppData\Roaming\npm-cache\strip-bom\2.0.0\package\package.json not in flight; writing
npm verb get https://registry.npmjs.org/parse-json not expired, no request
npm sill addNameRange number 2 { name: 'parse-json', range: '>=2.2.0 <3.0.0', hasData: true }
npm sill addNameRange versions [ 'parse-json',
npm sill addNameRange   [ '1.0.0', '1.0.1', '2.0.0', '2.1.0', '2.2.0' ] ]
npm sill addNamed parse-json@2.2.0
npm verb addNamed "2.2.0" is a plain semver version for parse-json
npm sill cache afterAdd parse-json@2.2.0
npm verb afterAdd C:\Users\Joram\AppData\Roaming\npm-cache\parse-json\2.2.0\package\package.json not in flight; writing
npm verb afterAdd C:\Users\Joram\AppData\Roaming\npm-cache\strip-bom\2.0.0\package\package.json written
npm verb afterAdd C:\Users\Joram\AppData\Roaming\npm-cache\parse-json\2.2.0\package\package.json written
npm sill fetchNamedPackageData error-ex
npm sill mapToRegistry name error-ex
npm sill mapToRegistry using default registry
npm sill mapToRegistry registry https://registry.npmjs.org/
npm sill mapToRegistry uri https://registry.npmjs.org/error-ex
npm verb request uri https://registry.npmjs.org/error-ex
npm verb request no auth needed
npm info attempt registry request try #1 at 15:49:36
npm verb request using bearer token for auth
npm verb etag "3KHL3H4PFPF45QUYUC5S0Q79R"
npm http request GET https://registry.npmjs.org/error-ex

npm-debug-2.log

npm info it worked if it ends with ok
npm verb cli [ 'C:\\Program Files\\nodejs\\node.exe',
npm verb cli   'C:\\Program Files\\nodejs\\node_modules\\npm\\bin\\npm-cli.js',
npm verb cli   'install',
npm verb cli   'grunt-contrib-uglify',
npm verb cli   '-g',
npm verb cli   '-ddd' ]
npm info using npm@3.3.6
npm info using node@v5.0.0
[...]
npm sill addNameRange     '1.1.2',
npm sill addNameRange     '1.1.3',
npm sill addNameRange     '1.2.0' ] ]
npm sill addNamed minimist@1.2.0
npm verb addNamed "1.2.0" is a plain semver version for minimist
npm sill cache afterAdd trim-newlines@1.0.0
npm verb afterAdd C:\Users\Joram\AppData\Roaming\npm-cache\trim-newlines\1.0.0\package\package.json not in flight; writing
npm sill cache afterAdd minimist@1.2.0
npm verb afterAdd C:\Users\Joram\AppData\Roaming\npm-cache\minimist\1.2.0\package\package.json not in flight; writing
npm verb afterAdd C:\Users\Joram\AppData\Roaming\npm-cache\trim-newlines\1.0.0\package\package.json written
npm verb afterAdd C:\Users\Joram\AppData\Roaming\npm-cache\minimist\1.2.0\package\package.json written

Meanwhile, node.js opens +- 60 TCP connections.