# X_UPGRADE_INSTALL_FAILED

## Means

bun install failed after x upgrade wrote the pins

## Typical cause

bun install exited non-zero: a package that no longer exists at the target version, a peer conflict, or the network. The pins and Bun floor are written and uncommitted

## Fix

`git restore .` — undoes the pins, since the tree was clean; then fix what the cause names and re-run: x upgrade --json

[CLI and verify](/error-codes#cli-and-verify)