[BUG] Claude Desktop MSIX: Recurring native crash on Windows with CJK username (v1.1.7053, Electron 40.4.1)

Bug description

Claude Desktop (MSIX/Store version) repeatedly enters a native crash loop on Windows when the Windows username contains CJK (Japanese) characters. The crash recurs periodically (every few weeks) and requires a full Remove-AppxPackage + reinstall cycle to resolve. This is not a one-time issue — it has happened twice on the same machine.

Environment

• OS: Windows 11 Pro 25H2 Build 26200
• Install type: MSIX (Microsoft Store)
• Username: Contains Japanese (CJK) characters
• Claude Desktop: v1.1.7053
• Electron: 40.4.1

Symptoms

• Native crash on every launch
• Main process initializes fully (all services, OAuth, CCD download start), then the renderer crashes
• Sentry captures: { type: 'Unknown', value: 'No message', stack: undefined } — no JS stack trace
• ~35MB crash dump (.dmp) generated each time

Timeline

| Date | Version | Behavior |
|------|---------|----------|
| 2026-03-10 | v1.1.5749 | Crash loop every 15-45s after launch |
| 2026-03-31 | v1.1.7053 (Electron 40.4.1) | Crash on every launch |

Both times resolved by the same workaround (see below). The crash returns after weeks of normal use.

Root cause analysis

The Electron generic_path() UTF-8 fix (electron/electron#48942, backported to 40-x-y) is included in Electron 40.4.1, yet the crash persists. This suggests additional Unicode path code paths in Claude Desktop's own application code that are not covered by the upstream Electron fix.

Related issues (all locked/closed)

• #28079 — Non-ASCII username crash (Korean) — locked
• #35366 — MSIX Korean username crash on restart — locked

Both were closed as fixed, but the underlying problem clearly persists across CJK languages and newer versions.

What does NOT work

• Clearing GPUCache / Cache / Code Cache / Crashpad
• --disable-gpu flag
• Full app data reset (Windows Settings > Apps > Claude > Reset)
• Reinstalling from Microsoft Store directly

The only reliable workaround

# Step 1: Remove the MSIX package
Get-AppxPackage -Name 'Claude' | Remove-AppxPackage

# Step 2: Reinstall via the stub installer (download from https://claude.ai/download)
Start-Process 'ClaudeSetup.exe'

This clears whatever corrupted state the MSIX virtualized filesystem accumulates. 2/2 success rate, but the fix is temporary — the crash returns after some period of normal use.

Expected behavior

Claude Desktop should launch and run stably on Windows systems where the username contains CJK/non-ASCII characters, without requiring periodic reinstallation.