I just tried installing webpack via npm in a new project and received the following. Notice the error in below near the end:
PS D:\Workspaces\profile-jsnelders-com> npm install webpack webpack-cli --save-dev
npm ERR! path D:\Workspaces\profile-jsnelders-com\node_modules\brorand\package.json.1891953989
npm ERR! code EPERM
npm ERR! errno -4048
npm ERR! syscall rename
npm ERR! Error: EPERM: operation not permitted, rename 'D:\Workspaces\profile-jsnelders-com\node_modules\brorand\package.json.1891953989' -> 'D:\Workspaces\profile-jsnelders-com\node_modules\brorand\package.json'
npm ERR! { Error: EPERM: operation not permitted, rename 'D:\Workspaces\profile-jsnelders-com\node_modules\brorand\package.json.1891953989' -> 'D:\Workspaces\profile-jsnelders-com\node_modules\brorand\package.json'
npm ERR! cause:
npm ERR! { Error: EPERM: operation not permitted, rename 'D:\Workspaces\profile-jsnelders-com\node_modules\brorand\package.json.1891953989' -> 'D:\Workspaces\profile-jsnelders-com\node_modules\brorand\package.json'
npm ERR! errno: -4048,
npm ERR! code: 'EPERM',
npm ERR! syscall: 'rename',
npm ERR! path: 'D:\\Workspaces\\profile-jsnelders-com\\node_modules\\brorand\\package.json.1891953989',
npm ERR! dest: 'D:\\Workspaces\\profile-jsnelders-com\\node_modules\\brorand\\package.json' },
npm ERR! stack: 'Error: EPERM: operation not permitted, rename \'D:\\Workspaces\\profile-jsnelders-com\\node_modules\\brorand\\package.json.1891953989\' -> \'D:\\Workspaces\\profile-jsnelders-com\\node_modules\\brorand\\package.json\'',
npm ERR! errno: -4048,
npm ERR! code: 'EPERM',
npm ERR! syscall: 'rename',
npm ERR! path: 'D:\\Workspaces\\profile-jsnelders-com\\node_modules\\brorand\\package.json.1891953989',
npm ERR! dest: 'D:\\Workspaces\\profile-jsnelders-com\\node_modules\\brorand\\package.json',
npm ERR! parent: 'profile-jsnelders-com' }
npm ERR!
npm ERR! The operation was rejected by your operating system.
npm ERR! It's possible that the file was already in use (by a text editor or antivirus),
npm ERR! or that you lack permissions to access it.
npm ERR!
npm ERR! If you believe this might be a permissions issue, please double-check the
npm ERR! permissions of the file and its containing directories, or try running
npm ERR! If you believe this might be a permissions issue, please double-check the
npm ERR! permissions of the file and its containing directories, or try running
npm ERR! the command again as root/Administrator (though this is not recommended).
npm ERR! A complete log of this run can be found in:
npm ERR! C:\Users\jsnel\AppData\Roaming\npm-cache\_logs\2020-02-06T20_06_02_861Z-debug.log
PS D:\Workspaces\profile-jsnelders-com> npm install webpack webpack-cli --save-dev
+ webpack@4.41.5
+ webpack-cli@3.3.10
added 10 packages from 6 contributors, updated 1 package and audited 8965 packages in 9.19s
found 0 vulnerabilities
PS D:\Workspaces\profile-jsnelders-com>
npm ERR! the command again as root/Administrator (though this is not recommended).
npm ERR! A complete log of this run can be found in:
npm ERR! C:\Users\jsnel\AppData\Roaming\npm-cache\_logs\2020-02-06T20_06_02_861Z-debug.log
I just re-ran the npm install ... again and it worked fine the second time. As the message suggests, it was probably a system process in Windows locking the file the first time.