Windows: Claude Code startup triggers 'Automatic file download' from Phone Link (on-demand cloud files)

Description

When Claude Code starts on Windows (native, not WSL), it triggers Windows "Automatic file download" notifications. The notification states that Claude Code is downloading files from a connected phone (via Phone Link / Your Phone app).

Notification message:

"Downloading YoonCheol's Note20 from Claude Code" 7 files, 641 KB

The downloads stop automatically after the initial startup scan completes. This only occurs during Claude Code's initialization phase.

Environment

• OS: Windows 11 Enterprise 10.0.26200
• Shell: Git Bash
• Phone Link: Active (Samsung Galaxy Note20 connected via Microsoft Phone Link)
• OneDrive: Not running

Root Cause Analysis

1. Phone Link exposes phone files (photos, screenshots, etc.) as on-demand cloud files on the Windows filesystem
2. When Claude Code starts, it scans configuration files, memory files, and project directories
3. This file scan inadvertently touches paths managed by Phone Link's on-demand file system
4. Windows Security shows the "Automatic file download" notification attributing the download to Claude Code
5. After the initial scan completes, no further downloads are triggered

Steps to Reproduce

1. Have Microsoft Phone Link active with a connected phone
2. Launch Claude Code on Windows (native)
3. Observe the "Automatic file download" notification from Windows

Expected Behavior

Claude Code's startup file scan should not trigger downloads of on-demand/cloud-backed files. Ideally, the scan should:

• Skip cloud-backed / on-demand file placeholders
• Or limit the scan scope to known Claude Code directories only

Actual Behavior

Claude Code scans broadly enough to touch Phone Link's on-demand files, triggering automatic downloads (~641KB, 7 files).

Impact

Low — the notification is cosmetic and the download stops quickly. However, it may confuse users and could potentially cause issues if the cloud file provider is unresponsive (e.g., contributing to "Service not responding" timeouts when WSL is also starting up).

Workaround

• Click "Allow" on the notification to whitelist Claude Code
• Or disable Phone Link auto-sync in Phone Link settings