pnpm "ERR_PNPM_UNEXPECTED_STORE" - Fix Store Path Mismatch in CI

pnpm links node_modules from a content-addressable store and records which store path it used. ERR_PNPM_UNEXPECTED_STORE means the existing node_modules was built against a different store than the one pnpm now resolves - usually a cache or path change between runs.

What this error means

pnpm install aborts with ERR_PNPM_UNEXPECTED_STORE, reporting that node_modules was created with a different store location. It commonly appears when a restored node_modules cache came from a runner with a different store path.

pnpm output

ERR_PNPM_UNEXPECTED_STORE  Unexpected store location
The node_modules was created using a different store path.
Current store: /home/runner/.pnpm-store/v3
Expected store: /root/.pnpm-store/v3

Common causes

node_modules restored from a different store path

A cached node_modules built where the pnpm store sat at one path is restored on a runner whose store path differs (different HOME/user), so the recorded store no longer matches.

The store path changed between runs

Changing store-dir, the HOME directory, or the user between runs moves the store, invalidating the link metadata in an existing node_modules.

How to fix it

Reset node_modules and pin the store path

Remove the mismatched node_modules and set a stable store directory.

Terminal

rm -rf node_modules
pnpm config set store-dir ~/.pnpm-store
pnpm install

Cache the store, not node_modules

Cache the pnpm store directory keyed on the lockfile, and let pnpm relink node_modules each run.
Set a fixed store-dir so its path does not vary by user/HOME.
Avoid restoring a node_modules built on a differently-pathed store.

How to prevent it

Pin store-dir to a stable path.
Cache the pnpm store, not node_modules.
Keep HOME/user consistent across CI runs.