npm publish causes 'Error: EPERM: operation not permitted, unlink ...', errno -4048

Question

I'm trying to publish my NPM package: npm publish.

I get the following quite cryptic error:

npm ERR! path c:\Temp\npm-20936-b98f84c8\tmp\fromDir-02dd5394\package.tgz
npm ERR! code EPERM
npm ERR! errno -4048
npm ERR! syscall unlink
npm ERR! Error: EPERM: operation not permitted, unlink 'c:\Temp\npm-20936-b98f84c8\tmp\fromDir-02dd5394\package.tgz'
npm ERR!     at Error (native)
npm ERR!  { Error: EPERM: operation not permitted, unlink 'c:\Temp\npm-20936-b98f84c8\tmp\fromDir-02dd5394\package.tgz'
npm ERR!     at Error (native)
npm ERR!   cause:
npm ERR!    { Error: EPERM: operation not permitted, unlink 'c:\Temp\npm-20936-b98f84c8\tmp\fromDir-02dd5394\package.tgz'
npm ERR!        at Error (native)
npm ERR!      errno: -4048,
npm ERR!      code: 'EPERM',
npm ERR!      syscall: 'unlink',
npm ERR!      path: 'c:\\Temp\\npm-20936-b98f84c8\\tmp\\fromDir-02dd5394\\package.tgz' },
npm ERR!   isOperational: true,
npm ERR!   stack: 'Error: EPERM: operation not permitted, unlink \'c:\\Temp\\npm-20936-b98f84c8\\tmp\\fromDir-02dd5394\\package.tgz\'\n    at Error (native)',
npm ERR!   errno: -4048,
npm ERR!   code: 'EPERM',
npm ERR!   syscall: 'unlink',
npm ERR!   path: 'c:\\Temp\\npm-20936-b98f84c8\\tmp\\fromDir-02dd5394\\package.tgz' }
npm ERR!
npm ERR! Please try running this command again as root/Administrator.

Tried running as admin - same error.

NPM version: 5.4.0

Node version: 6.11.1

OS: Windows 10

Any leads?

Answer 1

Silly me. The answer was in the docs all along.

In order to publish you need to be logged in from your NPM cli.

So either do npm login if you already have a user on npmjs.com, or npm adduser to create one.

I would, however, appreciate a more informative error message.