Unable to install Failed at the [email protected] postinstall script 'npm dedupe'.

[getsantanupathak]

npm install -g jupyter-dashboards-server
npm WARN deprecated [email protected]: update to @phosphor/signaling package
npm WARN deprecated [email protected]: update to @phosphor/disposable package
npm WARN deprecated [email protected]: package is no longer maintained
npm WARN deprecated [email protected]: update to @phosphor/application package
npm WARN deprecated [email protected]: update to @phosphor/properties package
npm WARN deprecated [email protected]: update to @phosphor/algorithm package
npm WARN deprecated [email protected]: use the @phosphor/ packages
npm WARN deprecated [email protected]: update to @phosphor/dragdrop package
npm WARN deprecated [email protected]: update to @phosphor/messaging package
npm WARN deprecated [email protected]: update to @phosphor/commands package
npm WARN deprecated [email protected]: update to @phosphor/widgets package
npm WARN deprecated [email protected]: update to @phosphor/widgets package
npm WARN deprecated [email protected]: update to @phosphor/widgets package
npm WARN deprecated [email protected]: update to @phosphor/collections package
npm WARN deprecated [email protected]: update to @phosphor/widgets package
/usr/bin/jupyter-dashboards-server -> /usr/lib/node_modules/jupyter-dashboards-server/bin/jupyter-dashboards-server

[email protected] install /usr/lib/node_modules/jupyter-dashboards-server/node_modules/websocket
(node-gyp rebuild 2> builderror.log) || (exit 0)

make: Entering directory /usr/lib/node_modules/jupyter-dashboards-server/node_modules/websocket/build' CXX(target) Release/obj.target/bufferutil/src/bufferutil.o SOLINK_MODULE(target) Release/obj.target/bufferutil.node COPY Release/bufferutil.node CXX(target) Release/obj.target/validation/src/validation.o SOLINK_MODULE(target) Release/obj.target/validation.node COPY Release/validation.node make: Leaving directory /usr/lib/node_modules/jupyter-dashboards-server/node_modules/websocket/build'

[email protected] postinstall /usr/lib/node_modules/jupyter-dashboards-server/node_modules/phosphor-dragdrop
npm dedupe

npm ERR! Linux 3.13.0-91-generic
npm ERR! argv "/usr/bin/nodejs" "/usr/bin/npm" "dedupe"
npm ERR! node v5.12.0
npm ERR! npm v3.8.6
npm ERR! path /root/.npm/_locks
npm ERR! code EACCES
npm ERR! errno -13
npm ERR! syscall mkdir

npm ERR! Error: EACCES: permission denied, mkdir '/root/.npm/_locks'
npm ERR! at Error (native)
npm ERR! { [Error: EACCES: permission denied, mkdir '/root/.npm/_locks']
npm ERR! errno: -13,
npm ERR! code: 'EACCES',
npm ERR! syscall: 'mkdir',
npm ERR! path: '/root/.npm/_locks' }
npm ERR!
npm ERR! Please try running this command again as root/Administrator.

npm ERR! Please include the following file with any support request:
npm ERR! /usr/lib/node_modules/jupyter-dashboards-server/node_modules/phosphor-dragdrop/npm-debug.log
/usr/lib
└── (empty)

npm ERR! Linux 3.13.0-91-generic
npm ERR! argv "/usr/bin/nodejs" "/usr/bin/npm" "install" "-g" "jupyter-dashboards-server"
npm ERR! node v5.12.0
npm ERR! npm v3.8.6
npm ERR! code ELIFECYCLE

npm ERR! [email protected] postinstall: npm dedupe
npm ERR! Exit status 243
npm ERR!
npm ERR! Failed at the [email protected] postinstall script 'npm dedupe'.
npm ERR! Make sure you have the latest version of node.js and npm installed.
npm ERR! If you do, this is most likely a problem with the phosphor-dragdrop package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR! npm dedupe
npm ERR! You can get information on how to open an issue for this project with:
npm ERR! npm bugs phosphor-dragdrop
npm ERR! Or if that isn't available, you can get their info via:
npm ERR! npm owner ls phosphor-dragdrop
npm ERR! There is likely additional logging output above.

npm ERR! Please include the following file with any support request:
npm ERR! /u0/sapathak/npm-debug.log
npm ERR! code 1

[drivaner]

Hi, similar issue here

npm ERR! Linux 4.4.0-31-generic
npm ERR! argv "/usr/bin/nodejs" "/usr/bin/npm" "install" "-g" "jupyter-dashboards-server"
npm ERR! node v6.10.3
npm ERR! npm v3.10.10
npm ERR! code ELIFECYCLE

npm ERR! [email protected] postinstall: npm dedupe
npm ERR! Exit status 243

Ubuntu-server 14.04.5 LTS

[drivaner]

Following solution worked fine for me:
https://docs.npmjs.com/getting-started/fixing-npm-permissions (part with option 2, steps 1-4)
just run npm install -g jupyter-dashboards-server without sudo