npm tried to change ownership of a file or directory but the OS/FS blocks lchown (common on Windows/WSL and non-root global prefixes). Use user-owned prefixes and avoid chown on unsupported filesystems.
npm occasionally calls lchown when installing globally or adjusting permissions in node_modules. On Windows/WSL and many container mounts, lchown is either unsupported or restricted, so the syscall returns EPERM and the install stops. This happens when installing globally as a non-root user, when the prefix is root-owned, inside Docker/CI with mismatched users, or on NTFS/SMB where chown semantics are limited. The fix is usually to avoid needing chown by keeping npm files in user-owned locations.
npm config get prefix
stat -f -c %T $(npm config get prefix) 2>/dev/null || stat -f $(npm config get prefix)mkdir -p ~/.npm-global
npm config set prefix ~/.npm-global
npm config set cache ~/.npm-cache
export PATH="$HOME/.npm-global/bin:$PATH"On NTFS/SMB mounts, chown is ignored or blocked. Install on a Linux/ext4 path (WSL ~/projects) or run without forcing ownership changes.
sudo rm -rf $(npm config get prefix)/lib/node_modules/.staging 2>/dev/null || true
npm cache clean --force
npm install -g <package>Run containers with matching UID/GID or chown the workspace/prefix once at startup so npm never needs to call lchown.
Homebrew installs under /opt/homebrew on macOS can drift to root-owned; prefer nvm/fnm to keep globals in $HOME and avoid chown. In CI, ensure the workspace is owned by the job user before npm ci; copying caches from root-owned layers often triggers lchown failures. On Windows/WSL, chown is largely a no-op—using per-user prefixes and avoiding sudo eliminates the syscall entirely.
npm notice access token expired or revoked. Please try logging in again.
Token has expired - npm authentication failure
npm ERR! code EAI_AGAIN
How to fix "EAI_AGAIN" in npm
npm error code E403 npm error 403 Forbidden - PUT https://registry.npmjs.org/<package>
How to fix 'E403 Forbidden' error in npm
npm ERR! code EUSAGE npm ERR! Usage error
How to fix "npm ERR! code EUSAGE" in Node.js projects
npm ERR! code E401 npm ERR! 401 Unauthorized
How to fix "E401 Unauthorized" in npm