@angular-devkit/core module not found after angular-cli global fresh install

Question

Using npm, I have installed angular-cli globally, with the command npm install -g @angular/cli.

After installing it succesfully, every command including just ng -v, returns the same error:

Error: Cannot find module '@angular-devkit/core'
Require stack:
- C:\Users\btngtk\AppData\Roaming\npm\node_modules\@angular\cli\lib\init.js
- C:\Users\btngtk\AppData\Roaming\npm\node_modules\@angular\cli\bin\ng
at Function.Module._resolveFilename (internal/modules/cjs/loader.js:623:15)?[39m
at Function.Module._load (internal/modules/cjs/loader.js:527:27)?[39m
at Module.require (internal/modules/cjs/loader.js:681:19)?[39m
at require (internal/modules/cjs/helpers.js:16:16)?[39m
    at Object.<anonymous> (C:\Users\btngtk\AppData\Roaming\npm\node_modules\?[4m@angular?[24m\cli\lib\init.js:13:16)
at Module._compile (internal/modules/cjs/loader.js:774:30)?[39m
at Object.Module._extensions..js (internal/modules/cjs/loader.js:785:10)?[39m
at Module.load (internal/modules/cjs/loader.js:641:32)?[39m
at Function.Module._load (internal/modules/cjs/loader.js:556:12)?[39m
at Module.require (internal/modules/cjs/loader.js:681:19)?[39m {
  code: ?[32m'MODULE_NOT_FOUND'?[39m,
  requireStack: [
    ?[32m'C:\\Users\\btngtk\\AppData\\Roaming\\npm\\node_modules\\@angular\\cli\\lib\\init.js'?[39m,
    ?[32m'C:\\Users\\btngtk\\AppData\\Roaming\\npm\\node_modules\\@angular\\cli\\bin\\ng'?[39m
  ]
}    

Answer 1

@angular-devkit is required by @angular/cli as dependency maybe something went wrong with npm install.

So uninstall @angular/cli with:

npm uninstall -g @angular/cli

Then clear the npm cache with:

npm cache clean --force

And then retry the installation.