[BUG] Claude Desktop installer (Claude Setup.exe) hangs indefinitely on Windows 11 — EventID 1002 Application Hang

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?

Title: Claude Desktop installer (Claude Setup.exe) hangs indefinitely on Windows 11 — EventID 1002 Application Hang

Environment:

Windows 11 Pro, Version 25H2 (OS Build 26200.9168)
Claude Setup.exe version attempted: 1.0.0.0
Installer downloaded fresh from claude.ai

Bug description:
Claude Desktop installer consistently hangs at the same step on every attempt. Download completes (3.36 MB), progress bar reaches the second/install stage, then freezes indefinitely with no further progress and no error message.

Event Viewer detail (EventID 1002, Application Hang):

AppName: Claude Setup.exe
AppVersion: 1.0.0.0
HangType: Top level window is idle

No exception code or fault module — this is a genuine UI-thread hang, not a crash, so no stack trace is available at the OS level.

Troubleshooting already completed (all reproduced the same hang):

Clean removal of all Claude/AnthropicClaude folders from %LOCALAPPDATA% and %APPDATA%, then fresh reinstall
Full system reboot
Reproduced via both the GUI installer and winget install Anthropic.Claude (including --verbose)
Windows Installer service found in a stopped state; restarted it — issue persisted
Windows Defender real-time protection fully disabled — issue persisted
Ruled out disk space (94GB free)
Confirmed not on a managed/corporate network — home network only
Killed all related processes (Claude Setup, msiexec) between attempts; none were hung/using CPU when checked afterward

Additional context:
Claude Desktop was previously working on this machine. Issue began when the app prompted a re-login mid-update, then errored with a generic "contact support" message. This is blocking use of MCP servers with Claude Desktop, which have no browser-based (claude.ai) equivalent.

What Should Happen?

Claude Desktop should install successfully on Windows 11 without the installer hanging.

Error Messages/Logs

Application Hang (EventID 1002):
AppName: Claude Setup.exe
AppVersion: 1.0.0.0
HangType: Top level window is idle
No exception code or fault module — this is a UI-thread hang, not a crash, so no stack trace is available.

Steps to Reproduce

1. Download Claude Setup.exe from claude.ai/download (Windows x64)
2. Right-click the installer and select "Run as administrator"
3. Accept the UAC prompt
4. Installer proceeds through the first progress bar quickly, then the second progress bar reaches 100% (download 3.36 MB of 3.36 MB) and hangs indefinitely
5. No error dialog appears — the window simply stops responding

This is fully reproducible:

• Clean install after removing all Claude/AnthropicClaude folders from %LOCALAPPDATA% and %APPDATA%
• After a full system reboot
• Via winget install Anthropic.Claude (including --verbose) in addition to the GUI installer
• With Windows Defender real-time protection disabled
• After confirming the Windows Installer service (was found stopped) is running

Event Viewer shows an Application Hang event (EventID 1002) rather than a crash — see Error Messages/Logs section.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

Unknown — app was working before this issue began, exact prior version not recorded

Claude Code Version

N/A — reporting a Claude Desktop (not Claude Code) installer issue

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_