Claude Code v2.1.61 Fixes Config File Corruption on Windows

Anthropic has released Claude Code v2.1.61, a targeted bugfix addressing a config file corruption issue on Windows.

The Fix: Concurrent Write Safety

The sole change in this release resolves a race condition where multiple Claude Code instances writing to the configuration file simultaneously could corrupt it on Windows. This scenario commonly arises when developers run Claude Code across multiple terminal windows or VS Code instances at the same time.

The fix implements proper file locking to ensure data integrity during concurrent access, eliminating a frustrating edge case that could leave users with broken configurations.

Context

This follows v2.1.59, which landed several notable features including auto-memory (Claude automatically saves useful context across sessions) and a new /copy command for selecting and copying code blocks from responses. With those features bedded in, v2.1.61 focuses purely on platform stability.

Windows users running multiple Claude Code instances should update promptly:

npm install -g @anthropic-ai/claude-code