Claude Code Windows Bug: Case-Sensitive File Tracker Causes 'File Has Not Been Read Yet' Error

What this error means

Claude Code Read/Edit tracker case-sensitive on Windows: drive-letter casing mismatch triggers 'File has not been read yet' is a Claude Code failure pattern reported for developers trying to fix claude code file has not been read yet windows / case-sensitive path error. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

Reported 2026-05-15: Case-sensitive path comparison on Windows breaks Read/Edit tracker. Reproducible bug with has-repro label.

Common causes

• On Windows, Claude Code’s internal file tracker uses case-sensitive string comparison. Because Windows filesystems are case-insensitive, ‘C:\file.txt’ and ‘c:\file.txt’ are treated as different files, causing persistent ‘File has not been read yet’ errors.
• Reported 2026-05-15: Case-sensitive path comparison on Windows breaks Read/Edit tracker. Reproducible bug with has-repro label.

Quick fixes

1. Confirm the exact error signature matches Claude Code Read/Edit tracker case-sensitive on Windows: drive-letter casing mismatch triggers 'File has not been read yet'.
2. Check the Claude Code account, local tool state, and provider configuration involved in the failing workflow.
3. Compare the failing environment with a known working setup, then change one configuration value at a time.

Platform/tool-specific checks

• Verify the command, editor, extension, or API client that produced the error.
• Compare local settings with CI, deployment, or editor-level settings when the error appears in only one environment.
• Avoid deleting credentials, local model data, or project settings until the failing scope is clear.

Step-by-step troubleshooting

1. Capture the exact error message and the command, editor action, or request that triggered it.
2. Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
3. Review the source evidence below and compare it with your environment.
4. Apply one change at a time and rerun the smallest failing action.
5. Keep the working fix documented for the team or deployment environment.

How to prevent it

• Keep provider/tool configuration documented.
• Record non-secret diagnostics such as tool version, provider name, model name, and command path.
• Add a lightweight check before CI or production workflows depend on the tool.

Sources checked

• https://github.com/anthropics/claude-code/issues/59362

Evidence note: Reported 2026-05-15: Case-sensitive path comparison on Windows breaks Read/Edit tracker. Reproducible bug with has-repro label.

Related errors

• Claude Code Windows file path errors
• Claude Code permission denied on Windows

FAQ

What should I check first?

Start with the exact Claude Code Read/Edit tracker case-sensitive on Windows: drive-letter casing mismatch triggers 'File has not been read yet' text and the smallest action that reproduces it.

Can I ignore this error?

No. Treat it as a failed Claude Code workflow until the root cause is understood.

Is this guaranteed to have one fix?

No. The imported evidence supports the troubleshooting path above, but tool behavior can vary by account, plan, version, provider, and local configuration.

How do I know the fix worked?

Rerun the same command, editor action, or request. The fix is working when that action completes without Claude Code Read/Edit tracker case-sensitive on Windows: drive-letter casing mismatch triggers 'File has not been read yet'.