Extremely slow startup on Windows due to tasklist command (~10 minutes)

Description

Claude Code startup is extremely slow on Windows (~10 minutes) due to the tasklist | findstr command used to detect running IDE processes.

Environment

• OS: Windows 10/11 (MINGW64_NT-10.0-26200)
• Claude Code Version: 2.0.76
• Shell: Git Bash

Evidence from Debug Log

2026-01-04T14:26:23.399Z [DEBUG] Loading skills from: ...
2026-01-04T14:36:23.291Z [DEBUG] [SLOW OPERATION DETECTED] execSyncWithDefaults_DEPRECATED (599879.9ms): tasklist | findstr /I "Code.exe Cursor.exe Windsurf.exe idea64.exe pycharm64.exe webstorm64.exe phps...

599,879.9ms = ~10 minutes for a single tasklist | findstr command.

Diagnosis Performed

1. WMI repository is consistent - winmgmt /verifyrepository returns OK
2. PowerShell Get-Process is fast - Only ~336ms
3. No antivirus interference - Exclusions added, no effect
4. System file check passed - sfc /scannow found no issues
5. Services restarted - No improvement

Root Cause

The tasklist command on Windows can be extremely slow in certain system configurations, while PowerShell's Get-Process works correctly.

Suggested Fix

Replace the slow tasklist | findstr pattern with PowerShell equivalent:

Current (slow):

tasklist | findstr /I "Code.exe Cursor.exe Windsurf.exe idea64.exe pycharm64.exe webstorm64.exe"

Suggested (fast, tested and working):

powershell -Command "Get-Process | Where-Object { $_.ProcessName -match 'Code|Cursor|Windsurf|idea64|pycharm64|webstorm64' }"

Benchmark on affected system:

• tasklist: ~600,000ms (10 minutes)
• Get-Process: ~336ms

Impact

• Users cannot use Claude Code effectively on affected Windows systems
• 10-minute startup delay makes the tool unusable

Workaround

None available - this is internal Claude Code behavior that users cannot modify.