Claude Desktop 1.1.9493.0 crashes on launch -- no UI rendered, main.log not created, Windows 11 Home 25H2

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Claude Desktop fails to launch after auto-updating to version 1.1.9493.0 on 30/03/2026. Every launch attempt immediately shows the error dialog "Claude Desktop failed to Launch. We are so sorry, Claude Desktop failed to launch. Please check for updates and try again." No UI is ever displayed. The app was working correctly on version 1.1.9134.0 two days prior.

What Should Happen?

Claude Desktop should launch normally and connect to CoworkVMService as it did on version 1.1.9134.0.

Claude Desktop version: 1.1.9493.0
Last working version: 1.1.9134.0
OS: Windows 11 Home
OS Version: 25H2
OS Build: 26200.8037
Processor: Intel Core i5-12600KF 3.70GHz
RAM: 32GB
Hyper-V: Not available (Windows Home edition)
VirtualMachinePlatform: Enabled
HypervisorPlatform: Enabled
Windows App Runtime 1.6: Installed

Error Messages/Logs

"We are so sorry, Claude Desktop failed to launch. Please check for updates and try again. If the issue persists, contact support."

main.log does not exist at:
C:\Users\[username]\AppData\Local\Packages\Claude_pzs8sxrjxfjjc\LocalCache\Roaming\Claude\logs\main.log
File absence confirms app crashes before any logging begins.
cowork-service.log confirms:

Service starts and reaches ready state on 30/03/2026 with version 1.1.9493.0
Claude Desktop never connects to the service (no RPC traffic, no VM callbacks)
On 27/03/2026 with version 1.1.9134.0 the app connected successfully and functioned normally

Steps to Reproduce

Auto-update from Claude Desktop 1.1.9134.0 to 1.1.9493.0 on Windows 11 Home 25H2
Launch Claude Desktop
Error dialog appears immediately -- no UI rendered

Started CoworkVMService manually via PowerShell -- service runs but app still fails
Enabled VirtualMachinePlatform and HypervisorPlatform Windows features
Installed Windows App Runtime 1.6
Full uninstall via Settings > Apps
Deleted AppData folders: %LOCALAPPDATA%\Packages\Claude_pzs8sxrjxfjjc and %APPDATA%\Claude
Fresh reinstall from claude.ai/download
Windows updated and rebooted
Issue persists through all steps

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

1.1.9134.0

Claude Code Version

N/A - Claude Desktop app issue, not Claude Code

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

Claude Desktop app fails to launch, not Claude Code CLI.

App version: 1.1.9493.0 (broken) -- auto-updated 30/03/2026
Last working: 1.1.9134.0 -- confirmed via cowork-service.log on 27/03/2026

OS: Windows 11 Home, 25H2, Build 26200.8037
CPU: Intel Core i5-12600KF
RAM: 32GB

main.log does not exist -- app crashes before any logging begins.
CoworkVMService starts and reaches ready state but Claude Desktop
never connects to it (no RPC traffic, no VM event callbacks).

Troubleshooting completed: CoworkVMService manually started,
VirtualMachinePlatform enabled, HypervisorPlatform enabled,
Windows App Runtime 1.6 installed, full uninstall + AppData
deletion + fresh reinstall -- issue persists through all steps.