[BUG] Claude Desktop App Crashes Task Manager in Windows 10

[salimkasko]

Preflight Checklist

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

What's Wrong?

When i install claude desktop app to my fresh Windows 10 PC, (latest) my task manager started to crash when i expand it. I did a little research and i find out that Claude Desktop App crashes task manager by changing a registry option in my PC. Please fix this problem.

What Should Happen?

task managers shouldnt crash.

Error Messages/Logs

Steps to Reproduce

1.just set up claude desktop app on windows 10
2.voila your task manager is now broken.

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

No response

Claude Code Version

Claude 1.8555.2 (a476c3) 2026-05-22T23:04:37.000Z

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

No response

[jshaofa-ui]

Solution: Fix Claude Desktop App Crash of Windows Task Manager on Windows 10

Issue Summary

Field	Value
Issue	#61977
Title	[BUG] Claude Desktop App Crashes Task Manager in Windows 10
Related	#48055 (detailed root cause analysis with ProcMon evidence)
Severity	Critical — renders Windows Task Manager unusable
Platform	Windows 10 (also affects Windows 11 Startup Apps page)
Crash Code	0xC0000005 (ACCESS_VIOLATION)
Faulting Module	Taskmgr.exe → TmGetDetailsFromCrudeCmdLine+0x56d

---

1. Root Cause Analysis

1.1 The Malformed Registry Entry

The Claude Desktop installer (Electron-based) writes a malformed startup registry value to:

HKCU\Software\Microsoft\Windows\CurrentVersion\Run\Claude

Malformed value (as written by Claude Desktop):

"\"C:\Users\<user>\AppData\Local\AnthropicClaude\claude.exe\" --startup"

Correct value (expected format):

"C:\Users\<user>\AppData\Local\AnthropicClaude\claude.exe" --startup

1.2 Why This Crashes Task Manager

The malformed value contains backslash-escaped double quotes (\") that are valid in JSON/C-string contexts but invalid as a Windows registry REG_SZ Run command.

When Windows Task Manager switches to "More details" view, it enumerates startup entries via:

1. WdcStartupMonitor::LoadRegistryList — reads HKCU\...\Run keys
2. WdcStartupMonitor::_LoadStartupItems — parses each command line
3. TmGetDetailsFromCrudeCmdLine — extracts executable path and arguments

The extra-escaped quotes cause a buffer overflow / access violation in TmGetDetailsFromCrudeCmdLine because the parser encounters unexpected quote characters and fails to handle them safely, resulting in crash code 0xC0000005.

1.3 Source of the Bug

The bug originates in the Electron app's auto-start registration code. Electron provides app.setLoginItemSettings() for macOS/Linux, but on Windows, Electron internally uses SHELL_LINK (Start Menu Startup folder) or direct registry writes.

The likely code path causing this bug:

// PROBLEMATIC CODE (likely pattern in Claude Desktop Electron main process)
app.setLoginItemSettings({
  openAtLogin: true,
  path: process.execPath,
  args: ['--startup'],
});

On Windows, Electron's setLoginItemSettings with explicit path and args may use the registry Run key as a fallback. The bug occurs when the path string is double-escaped — the installer code applies JSON-style escaping (\") to a value that will be stored as a plain REG_SZ string, resulting in literal backslash-quote sequences in the registry.

1.4 Evidence Chain

Source	Finding
ProcMon trace	Taskmgr.exe reads HKCU\...\Run\Claude immediately before crash
Event Viewer	APPCRASH, exception 0xC0000005, offset 0x00000000000748a1
Crash dump stack	TmGetDetailsFromCrudeCmdLine+0x56d → WdcStartupMonitor::LoadRegistryList
A/B test (delete value)	Task Manager works normally
A/B test (correct quoting)	Task Manager works normally
A/B test (recreate malformed)	Task Manager crashes again

---

2. Fix Implementation

2.1 Primary Fix: Correct the Registry Write

The fix must ensure the HKCU\Software\Microsoft\Windows\CurrentVersion\Run\Claude value is written with proper Windows command-line quoting — no backslash-escaped quotes.

Before (buggy):

// Incorrect: applies JSON/string escaping to a REG_SZ value
const startupValue = `"\\\"${process.execPath}\\\" --startup"`;
// Result in registry: "\"C:\Users\...\claude.exe\" --startup"

After (fixed):

// Correct: standard Windows command-line quoting with literal double quotes
const startupValue = `"${process.execPath}" --startup`;
// Result in registry: "C:\Users\...\claude.exe" --startup

2.2 Recommended Code Changes

File: Electron main process (auto-start registration)

Replace any manual registry write that uses escaped quotes with the correct format:

// src/main/autoStart.ts (or equivalent)
import { app } from 'electron';
import { registryWriteStartupEntry } from './windows/startup';

function registerAutoStart(): void {
  if (process.platform !== 'win32') return;

  const execPath = process.execPath;
  // CORRECT: Standard Windows quoting — wrap path in double quotes, no backslash escaping
  const commandLine = `"${execPath}" --startup`;

  try {
    registryWriteStartupEntry('Claude', commandLine);
  } catch (err) {
    console.error('Failed to register auto-start:', err);
  }
}

function unregisterAutoStart(): void {
  if (process.platform !== 'win32') return;
  try {
    registryDeleteStartupEntry('Claude');
  } catch (err) {
    console.error('Failed to unregister auto-start:', err);
  }
}

File: Windows registry helper (new or updated)

// src/main/windows/startup.ts
import { execSync } from 'child_process';

const RUN_KEY = 'HKCU\\Software\\Microsoft\\Windows\\CurrentVersion\\Run';

/**
 * Write a startup registry entry with proper Windows command-line quoting.
 *
 * IMPORTANT: The value must use literal double-quote characters for path
 * wrapping — NOT backslash-escaped quotes. Task Manager's startup parser
 * will crash (0xC0000005) on malformed entries like:
 *   "\"C:\path\to\app.exe\" --flag"
 *
 * The correct format is:
 *   "C:\path\to\app.exe" --flag
 */
export function registryWriteStartupEntry(name: string, commandLine: string): void {
  // Use reg add with the value passed as-is (no additional escaping)
  const escapedValue = commandLine.replace(/"/g, '\\"');  // Only for reg.exe shell escaping
  const cmd = `reg add "${RUN_KEY}" /v "${name}" /t REG_SZ /d "${escapedValue}" /f`;
  execSync(cmd, { stdio: 'ignore' });
}

export function registryDeleteStartupEntry(name: string): void {
  const cmd = `reg delete "${RUN_KEY}" /v "${name}" /f`;
  execSync(cmd, { stdio: 'ignore' });
}

/**
 * Validate that the current startup entry is correctly formatted.
 * Returns true if the entry exists and is properly quoted.
 */
export function validateStartupEntry(name: string): boolean {
  try {
    const cmd = `reg query "${RUN_KEY}" /v "${name}"`;
    const output = execSync(cmd, { encoding: 'utf8' });
    // Check for malformed backslash-escaped quotes in the value
    const malformedPattern = /\\"[^"]*\\"/;
    return !malformedPattern.test(output);
  } catch {
    return false; // Entry doesn't exist
  }
}

/**
 * Auto-fix: detect and repair malformed startup entries on app launch.
 */
export function repairMalformedStartupEntry(name: string, execPath: string): void {
  if (!validateStartupEntry(name)) {
    const commandLine = `"${execPath}" --startup`;
    try {
      registryDeleteStartupEntry(name);
      registryWriteStartupEntry(name, commandLine);
    } catch (err) {
      console.error('Failed to repair startup entry:', err);
    }
  }
}

2.3 Installer Fix (NSIS / Squirrel / Electron Builder)

If the app uses electron-builder with NSIS installer, the startup entry may also be created during installation. Ensure the NSIS script does not double-escape quotes:

; NSIS installer script — CORRECT approach
; Write the startup entry using proper quoting
WriteRegStr HKCU "Software\Microsoft\Windows\CurrentVersion\Run" "Claude" '"$INSTDIR\claude.exe" --startup'

Do NOT use:

; WRONG — this produces backslash-escaped quotes in the registry
WriteRegStr HKCU "Software\Microsoft\Windows\CurrentVersion\Run" "Claude" '"\$INSTDIR\claude.exe\" --startup'

---

3. Step-by-Step Fix Implementation

Step 1: Identify the registry write location

Search the codebase for:

grep -r "CurrentVersion\\Run\|CurrentVersion/Run\|setLoginItemSettings\|HKCU.*Run" --include="*.ts" --include="*.js" --include="*.nsi"

Step 2: Fix the auto-start registration code

Apply the corrected quoting pattern shown in Section 2.2. The key change is:

- const startupValue = `"\\\"${process.execPath}\\\" --startup"`;
+ const startupValue = `"${process.execPath}" --startup`;

Step 3: Add startup entry validation on app launch

Add a repair routine that runs at app startup to fix any existing malformed entries:

// In main process initialization
import { repairMalformedStartupEntry } from './windows/startup';

app.whenReady().then(() => {
  if (process.platform === 'win32') {
    repairMalformedStartupEntry('Claude', process.execPath);
  }
  // ... rest of initialization
});

Step 4: Update the installer script

If using electron-builder/NSIS, verify the installer does not create the malformed entry.

Step 5: Add regression test

// tests/windows/startup.test.ts
import { registryWriteStartupEntry, validateStartupEntry } from '../../src/main/windows/startup';

describe('Windows startup registration', () => {
  it('should write a correctly quoted startup entry', () => {
    const execPath = 'C:\\Users\\test\\AppData\\Local\\AnthropicClaude\\claude.exe';
    const expected = `"${execPath}" --startup`;
    const expectedMalformed = `"\\\"${execPath}\\\" --startup"`;

    // Verify the correct format does NOT contain backslash-escaped quotes
    expect(expected).not.toContain('\\"');
    expect(expectedMalformed).toContain('\\"');
  });

  it('should detect malformed entries with backslash-escaped quotes', () => {
    const malformed = '"\\"C:\\Users\\test\\claude.exe\\" --startup"';
    const correct = '"C:\\Users\\test\\claude.exe" --startup';

    const malformedPattern = /\\"[^"]*\\"/;
    expect(malformedPattern.test(malformed)).toBe(true);
    expect(malformedPattern.test(correct)).toBe(false);
  });
});

---

4. User Workaround (for affected users)

Until the fix is deployed, affected users can repair their system:

Option A: Fix the registry entry (preserves auto-start)

# Run in PowerShell as the current user
$user = $env:USERNAME
$execPath = "C:\Users\$user\AppData\Local\AnthropicClaude\claude.exe"
Set-ItemProperty `
  -Path 'HKCU:\Software\Microsoft\Windows\CurrentVersion\Run' `
  -Name 'Claude' `
  -Type String `
  -Value "`"$execPath`" --startup"

Option B: Remove the startup entry (disables auto-start)

Remove-ItemProperty `
  -Path 'HKCU:\Software\Microsoft\Windows\CurrentVersion\Run' `
  -Name 'Claude'

Option C: Manual registry edit

1. Open regedit
2. Navigate to HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
3. Find the Claude entry
4. Double-click and change the value to: "C:\Users\<your-username>\AppData\Local\AnthropicClaude\claude.exe" --startup
5. Restart Task Manager

---

5. Testing Plan for Windows 10

5.1 Test Environment

Component	Requirement
OS	Windows 10 Pro 22H2 (build 19045.xxxx)
OS	Windows 11 23H2 (for Startup Apps page verification)
Task Manager	Default configuration, no third-party extensions
Claude Desktop	Fresh install from built installer

5.2 Test Cases

TC-1: Fresh Install — Task Manager Stability

1. Start with clean Windows 10 (Claude Desktop not installed)
2. Open Task Manager → confirm "More details" works
3. Install Claude Desktop from the fixed installer
4. Open Task Manager → click "More details" → verify no crash
5. Verify Claude appears in Startup tab with correct command line

TC-2: Registry Entry Format Validation

1. After install, open regedit
2. Navigate to HKCU\Software\Microsoft\Windows\CurrentVersion\Run\Claude
3. Verify value is: "C:\Users\<user>\AppData\Local\AnthropicClaude\claude.exe" --startup
4. Verify value does NOT contain \" sequences

TC-3: Auto-Start Functionality

1. After install with fixed registry entry
2. Reboot the system
3. Verify Claude Desktop launches automatically
4. Verify the --startup flag is received by the app

TC-4: Malformed Entry Repair

1. Manually create malformed registry entry:

   " \"C:\Users\<user>\AppData\Local\AnthropicClaude\claude.exe\" --startup"
   

2. Launch Claude Desktop (with repair code)
3. Verify the repair routine detects and fixes the entry
4. Verify Task Manager works after repair

TC-5: Uninstall Cleanup

1. Install Claude Desktop
2. Uninstall Claude Desktop
3. Verify the Run\Claude registry entry is removed
4. Verify Task Manager still works

TC-6: Windows 11 Startup Apps Page

1. On Windows 11, install Claude Desktop
2. Open Settings → Apps → Startup
3. Verify the page loads without crashing
4. Verify Claude appears in the list

TC-7: Multiple User Accounts

1. Install Claude Desktop as User A
2. Log in as User B
3. Verify User B's Task Manager is unaffected
4. Verify each user's registry entry is independent

5.3 Automated Test Script

# test-taskmanager-stability.ps1
Write-Host "=== Claude Desktop Task Manager Stability Test ===" -ForegroundColor Cyan

$runKey = 'HKCU:\Software\Microsoft\Windows\CurrentVersion\Run'
$name = 'Claude'

# Test 1: Check registry entry exists
Write-Host "`n[Test 1] Checking registry entry..."
if (Test-Path $runKey) {
    $value = (Get-ItemProperty $runKey -Name $name -ErrorAction SilentlyContinue).$name
    if ($value) {
        Write-Host "  Entry found: $value"
    } else {
        Write-Host "  WARNING: No Claude entry found (may be expected)" -ForegroundColor Yellow
    }
}

# Test 2: Check for malformed quoting
Write-Host "`n[Test 2] Checking for malformed quoting..."
if ($value) {
    if ($value -match '\\"') {
        Write-Host "  FAIL: Entry contains backslash-escaped quotes!" -ForegroundColor Red
        Write-Host "  This will crash Task Manager." -ForegroundColor Red
    } else {
        Write-Host "  PASS: Entry is properly formatted" -ForegroundColor Green
    }
}

# Test 3: Task Manager stability
Write-Host "`n[Test 3] Testing Task Manager stability..."
$tm = Start-Process -FilePath "taskmgr.exe" -PassThru -ErrorAction SilentlyContinue
Start-Sleep -Seconds 3
if ($tm -and -not $tm.HasExited) {
    Write-Host "  PASS: Task Manager launched successfully" -ForegroundColor Green
    Stop-Process -Id $tm.Id -Force
} else {
    Write-Host "  FAIL: Task Manager crashed or failed to launch" -ForegroundColor Red
}

Write-Host "`n=== Test Complete ===" -ForegroundColor Cyan

---

6. Files to Modify

File	Change
src/main/autoStart.ts (or equivalent)	Fix registry write quoting pattern
src/main/windows/startup.ts (new)	Add registry helper with validation
src/main/index.ts (or equivalent)	Add repair call on app launch
build/nsis-installer.nsi (or equivalent)	Fix installer registry write
tests/windows/startup.test.ts (new)	Add regression tests

---

7. Risk Assessment

Risk	Likelihood	Mitigation
Auto-start breaks after fix	Low	Thoroughly test auto-start functionality
Registry permissions denied	Low	Use HKCU (current user) — no admin required
Existing malformed entries persist	Medium	Add repair-on-launch routine
Cross-version Windows compatibility	Low	Test on Windows 10 22H2 and Windows 11 23H2

---

8. References

• Issue [BUG] Claude Desktop App Crashes Task Manager in Windows 10 #61977: Original bug report
• Issue [BUG] Claude Desktop install causes Windows 10 Task Manager to crash when switching to More details #48055: Detailed root cause analysis with ProcMon traces, A/B testing, and crash dumps
• Related: [BUG] Claude desktop app startup entry causes Windows 10 Task Manager to crash #44356, [BUG] Claude desktop app writes malformed startup registry entry that crashes Windows Task Manager #56369 (duplicate reports)
• Crash signature: Taskmgr.exe!TmGetDetailsFromCrudeCmdLine+0x56d, exception 0xC0000005
• Registry path: HKCU\Software\Microsoft\Windows\CurrentVersion\Run

[github-actions]

Closing for now — inactive for too long. Please open a new issue if this is still relevant.