Npm not being able to find a file - Installing bcrypt - node.js

Question

I'm having an issue with installing Bcrypt via NPM.
Installing it using the command npm install bcrypt gives the following:
npm WARN lifecycle npm is using /opt/plesk/node/7/bin/node but there is no node binary in the current PATH. Use the `--scripts-prepend-node-path` option to include the path for the node binary npm was executed with.
> bcrypt#3.0.6 install /var/www/vhosts/mydomain/node_modules/bcrypt
> node-pre-gyp install --fallback-to-build
/usr/bin/env: node: No such file or directory
npm WARN enoent ENOENT: no such file or directory, open '/var/www/vhosts/mydomain/package.json'
npm WARN mydomain No description
npm WARN mydomain No repository field.
npm WARN mydomain No README data
npm WARN mydomain No license field.
npm ERR! Linux 3.10.0-042stab140.1
npm ERR! argv "/opt/plesk/node/7/bin/node" "/opt/plesk/node/7/bin/npm" "install" "bcrypt"
npm ERR! node v7.4.0
npm ERR! npm v4.0.5
npm ERR! file sh
npm ERR! code ELIFECYCLE
npm ERR! errno ENOENT
npm ERR! syscall spawn
npm ERR! bcrypt#3.0.6 install: `node-pre-gyp install --fallback-to-build`
npm ERR! spawn ENOENT
npm ERR!
npm ERR! Failed at the bcrypt#3.0.6 install script 'node-pre-gyp install --fallback-to-build'.
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 bcrypt package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR! node-pre-gyp install --fallback-to-build
npm ERR! You can get information on how to open an issue for this project with:
npm ERR! npm bugs bcrypt
npm ERR! Or if that isn't available, you can get their info via:
npm ERR! npm owner ls bcrypt
npm ERR! There is likely additional logging output above.
I have run npm bugs bcrypt and my server has also spit out the following:
npm ERR! Linux 3.10.0-042stab140.1
npm ERR! argv "/opt/plesk/node/7/bin/node" "/opt/plesk/node/7/bin/npm" "bugs" "bcrypt"
npm ERR! node v7.4.0
npm ERR! npm v4.0.5
npm ERR! path xdg-open
npm ERR! code ENOENT
npm ERR! errno ENOENT
npm ERR! syscall spawn xdg-open
npm ERR! enoent spawn xdg-open ENOENT
npm ERR! enoent spawn xdg-open ENOENT
npm ERR! enoent This is most likely not a problem with npm itself
npm ERR! enoent and is related to npm not being able to find a file.
npm ERR! enoent
Any ideas as to what's going on? Is there a compatibility issue to the version of NPM or Node that I'm running?
Any help is appreciated :)
Cheers