[BUG]

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 won’t launch and shows “Claude Desktop failed to launch. Please check for updates and try again.”
Environment:
Desktop app version: 1.1617.0.0
OS: Windows (please add 10 or 11)
Exact error message: “Claude Desktop failed to launch”
Logs (Event Viewer):
Faulting application name: Claude.exe, version: 1.1617.0.0, time stamp: 0x69c47a74
Faulting module name: CoreMessaging.dll, version: 10.0.19041.5915, time stamp: 0x0bfde6dc
Exception code: 0xc0000602
Fault offset: 0x0000000000072e16
Faulting process id: 0x3784
Faulting application start time: 0x01dccb3023896fa5
Faulting application path: C:\Program Files\WindowsApps\Claude_1.1617.0.0_x64__pzs8sxrjxfjjc\app\Claude.exe
Faulting module path: C:\Windows\System32\CoreMessaging.dll
Report Id: 84946c61-8489-4df2-ad04-3bb76b35dfb4
Faulting package full name: Claude_1.1617.0.0_x64__pzs8sxrjxfjjc
Faulting package-relative application ID: Claude

What Should Happen?

Here’s a ready-to-paste bug report you can submit on GitHub (or via /bug in Claude Code if you can access it).
Subject: Claude Desktop fails to launch on Windows (CoreMessaging.dll crash)
Description:
Claude Desktop won’t launch and shows “Claude Desktop failed to launch. Please check for updates and try again.”
Environment:
Desktop app version: 1.1617.0.0
OS: Windows (please add 10 or 11)
Exact error message: “Claude Desktop failed to launch”
Logs (Event Viewer):
Faulting application name: Claude.exe, version: 1.1617.0.0, time stamp: 0x69c47a74
Faulting module name: CoreMessaging.dll, version: 10.0.19041.5915, time stamp: 0x0bfde6dc
Exception code: 0xc0000602
Fault offset: 0x0000000000072e16
Faulting process id: 0x3784
Faulting application start time: 0x01dccb3023896fa5
Faulting application path: C:\Program Files\WindowsApps\Claude_1.1617.0.0_x64__pzs8sxrjxfjjc\app\Claude.exe
Faulting module path: C:\Windows\System32\CoreMessaging.dll
Report Id: 84946c61-8489-4df2-ad04-3bb76b35dfb4
Faulting package full name: Claude_1.1617.0.0_x64__pzs8sxrjxfjjc
Faulting package-relative application ID: Claude

Error Messages/Logs

Steps to Reproduce

Here are clear, numbered steps anyone can follow to reproduce the “Claude Desktop failed to launch” issue on Windows.
Install Claude Desktop on Windows (any version, but note the version you install).
Fully close any running Claude Desktop process (if it opens at all).
Launch Claude Desktop again.
Observe the error dialog: “Claude Desktop failed to launch. Please check for updates and try again.”
Open Windows Event Viewer → Windows Logs → Application.
Find the latest Claude Desktop crash entry and confirm it shows a fault in CoreMessaging.dll (example: Exception code 0xc0000602).
No special code or files are needed to reproduce this - it’s a launch crash.

Claude Model

None

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

1.1617.0.0.

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

_No response_