How to fix npm ERR! Error: EPERM: operation not permitted, mkdir '<path>' in npm

npmBEGINNERMEDIUM

npm cannot create a directory because the filesystem or policy blocks it (Windows/WSL AV locks, root-owned prefixes, read-only mounts). Use user-owned paths, release locks, and retry.

What this error means

mkdir failed before permission checks completed, usually because Windows/WSL policy or locks blocked directory creation. npm hits this when writing to node_modules, cache, or global prefixes that are locked by AV, owned by another user, or on restricted mounts. It is frequent on Windows with Defender/EDR, WSL2 on /mnt/c, and Docker/CI when running as a different user than the volume owner. Root-owned remnants from earlier sudo installs can also cause mkdir to be rejected.

Typical symptoms

npm install/ci fails with EPERM: mkdir '<path>'
Works with sudo/Admin but fails otherwise
node_modules/.staging or cache dirs persist across failures
Defender/AV alerts when npm runs
Happens more on Windows/WSL/network paths than local ext4

Common causes

AV/EDR or file watchers locking directories during creation
Root-owned global prefix or node_modules from prior sudo installs
NTFS/SMB mounts (WSL2, network shares) denying mkdir
Docker/CI UID mismatch with mounted workspace
Read-only or quota-limited filesystem

How to fix "npm ERR! Error: EPERM: operation not permitted, mkdir '<path>'"

1Check path ownership and free space

bash

ls -ld <path> || true
stat $(dirname <path>)
df -h <path>

2Release AV/IDE locks

Close VS Code/terminals, add Defender/AV exclusions for the project and npm cache, then retry.

3Use user-owned cache/prefix and clean temp dirs

bash

npm config set cache ~/.npm-cache
mkdir -p ~/.npm-global
npm config set prefix ~/.npm-global
export PATH="$HOME/.npm-global/bin:$PATH"
rm -rf node_modules/.staging 2>/dev/null || true

4Work on writable filesystems

On WSL, move the repo to ext4 (~/projects). In Docker, run with matching UID/GID or chown the bind mount.

Advanced notes

Corporate laptops sometimes apply AppLocker/Controlled Folder Access, blocking mkdir in developer directories; adding approved exclusions or using user-owned prefixes in $HOME avoids the policy. In CI, make sure the workspace isn’t mounted read-only and that earlier root steps didn’t leave .staging directories. For Windows long-path scenarios, enabling longPaths in git and npm can help but the primary fix is using a shorter, user-writable path.

Related errors

Official resources & further reading

📚npm Official Documentation
📖
Microsoft Docs: WSL file permission considerations(Official Docs)
📖
npm Docs: Permissions guidance(Official Docs)
💬
Stack Overflow: Permission denied mkdir in npm install(Stack Overflow)
🐙
npm/cli#3618 - permissions in npm cache/node_modules(GitHub)