npm - not installed; illegal characters in path - json

Question

Inherited a broken NLog project from a long-gone co-worker...
VS2015 update 2
Latest Node install
Latest npm update 3.10.3
'.net 5.0' project (pre-core 1.0)
My npm node always says 'npm - not installed'
When I right click, I instantly get 'illegal characters in path'
here's my package.json
{
"version": "0.0.0",
"name": "asp.net",
"devDependencies": {
"gulp": "^3.9.0",
"gulp-bower": "^0.0.11",
"gulp-concat": "^2.6.0",
"gulp-install": "^0.6.0",
"gulp-sass": "^2.1.1",
"gulp-uglify": "^1.5.1",
"gulp-util": "^3.0.7",
"gulp-watch": "^4.3.5",
"run-sequence": "^1.1.5",
"browser-sync": "^2.10.0",
"gulp-filter": "^3.0.1",
"main-bower-files": "^2.9.0",
"gulp-rename": "^1.2.2",
"gulp-sourcemaps": "^1.6.0"
}
here's my project.json:
{
"webroot": "wwwroot",
"version": "1.0.0-*",
"dependencies": {
"EntityFramework.Commands": "7.0.0-rc1-final",
"EntityFramework.MicrosoftSqlServer": "7.0.0-rc1-final",
"Microsoft.AspNet.Authentication.Cookies": "1.0.0-rc1-final",
"Microsoft.AspNet.Diagnostics": "1.0.0-rc1-final",
"Microsoft.AspNet.Diagnostics.Entity": "7.0.0-rc1-final",
"Microsoft.AspNet.Identity.EntityFramework": "3.0.0-rc1-final",
"Microsoft.AspNet.IISPlatformHandler": "1.0.0-rc1-final",
"Microsoft.AspNet.Mvc": "6.0.0-rc1-final",
"Microsoft.AspNet.Mvc.TagHelpers": "6.0.0-rc1-final",
"Microsoft.AspNet.Server.Kestrel": "1.0.0-rc1-final",
"Microsoft.AspNet.Server.WebListener": "1.0.0-rc1-final",
"Microsoft.AspNet.Session": "1.0.0-rc1-final",
"Microsoft.AspNet.SignalR.Server": "3.0.0-rc1-final",
"Microsoft.AspNet.StaticFiles": "1.0.0-rc1-final",
"Microsoft.AspNet.Tooling.Razor": "1.0.0-rc1-final",
"Microsoft.Extensions.Caching.Memory": "1.0.0-rc1-final",
"Microsoft.Extensions.Configuration.Json": "1.0.0-rc1-final",
"Microsoft.Extensions.Logging": "1.0.0-rc1-final",
"Microsoft.Extensions.Logging.Console": "1.0.0-rc1-final",
"Microsoft.Extensions.Logging.Debug": "1.0.0-rc1-final",
"Microsoft.Extensions.Logging.NLog": "1.0.0-rc1-final",
"Microsoft.VisualStudio.Web.BrowserLink.Loader": "14.0.0-rc1-final",
"MvcWebApiCors": "0.3.0"
},
"commands": {
"web": "Microsoft.AspNet.Server.Kestrel",
"ef": "EntityFramework.Commands"
},
"frameworks": {
"dnx451": {
"dependencies": {
"Rally.RestApi": "1.0.0-*"
}
}
},
"exclude": [
"wwwroot",
"node_modules",
"bower_components"
],
"publishExclude": [
"node_modules",
"bower_components",
"**.kproj",
"**.user",
"**.vspscc"
],
"scripts": {
"postrestore": [ "npm install" ],
"prepare": [ "gulp" ]
}
Here's my Bower.json
{
"name": "WebApplication",
"private": true,
"dependencies": {
"bootstrap": "^4.0.0-alpha.2",
"signalr": "^2.2.0",
"font-awesome": "^4.5.0",
"moment": "^2.11.0",
"Chart-js": "^1.0.2",
"tether": "^1.1.1",
"bootstrap-daterangepicker": "2.1.17",
"handlebars": "^4.0.5",
"chosen": "^1.4.2"
}
global.json
{
"projects": [
"src",
"wrap"
],
"sdk": {
"version": "1.0.0-rc1-update1"
}
The overall problem is that none of the css/styles are showing. The site looks skeletal compared to what's on our iis box.

Answer 1

Faced the same issue when tried to install an npm package globally (with -g flag).
Any npm package which I tried to install globally was throwing the same error given below.
npm ERR! code EINVAL
npm ERR! path C:\Users\xxxxxxx'C:\Users\xxxxxxx\AppData\Roaming\npm
npm ERR! Illegal characters in path.
npm ERR! A complete log of this run can be found in:
npm ERR! C:\Users\xxxxxxx\AppData\Local\npm-cache\_logs\2021-12-15T10_49_39_874Z-debug.log
I checked the PATH variable. All is well.
After some research over the internet, tried the following command
npm bin -g
This showed a weird path.
C:\Users\xxxxxx'C:\Users\xxxxxx\AppData\Roaming\npm
(not in PATH env variable)
After reading this post, I tried to set the path prefix of npm config and it worked!
This is how I set it.
npm config set prefix C:\Users\xxxxxxx\AppData\Roaming\npm
You can check & confirm the same using,
npm config get prefix
Ideally, this path was getting added to the '.npmrc' file in my home directory (C:\Users\xxxxxxx). If you don't have any other content in the '.npmrc' file (like an access token to your private npm registry), deleting the file will fix this issue.
Just posting here, so that someone facing similar issue might find
this helpful as the question title relates to this issue.

Answer 2

Found the answer...
Some packages (for instance webpack) have dependency on packages that are not supported on windows which causes NPM to print warning about it. VS interprets it as generic problem and says that packages are not installed even though in reality this warning should be ignored.