# 🚀 New Release: mcp-windbg 1.2.2

> A fix for missing Unicode output on Chinese, Japanese, and Korean Windows systems.

- Published: 2026-09-05
- Author: Sven Scharmentke
- Canonical: https://svnscha.de/posts/mcp-windbg-1-2-2-release/
- Tags: ai, debugging, mcp-windbg, copilot, crash-analysis, community, release

---

Version 1.2.2 of **mcp-windbg** is out. This release fixes missing Unicode output on Windows systems that use a multibyte code page, including Chinese, Japanese, and Korean systems.

The bug was reported by a community member in [issue #102](https://github.com/svnscha/mcp-windbg/issues/102). Thanks for taking the time to provide a clear report and help track it down.

## The Problem

The `du` command, which displays a Unicode string, sometimes returned an empty result through mcp-windbg. Running the same command directly in CDB worked as expected. Other commands such as `db` and `dw` also worked against the same address.

The important detail was the reporter's Chinese Windows system locale.

## What Caused It

mcp-windbg communicates with `cdb.exe` through a pipe. It sends a command and reads the debugger's response from that pipe.

On multibyte system code pages, such as Chinese 936, Japanese 932, Korean 949, or the "Use Unicode UTF-8" setting, CDB can truncate text while writing it to a pipe. The end of a line may be missing, including the closing quote and newline.

For `du`, this could remove the entire string. If the output was cut in the middle of a character, later commands could also time out because the session could no longer parse the incomplete output correctly.

This only affects redirected output, which is why the command still looks correct when run in a normal debugger window. There is no CDB option that fixes the pipe output; interactive mode, batch mode, and ANSI log files all show the same problem.

## The Fix

CDB can write complete UTF-16 log files using `.logopen /u`, so mcp-windbg now uses one on affected systems. The pipe is still used to manage command timing, but the command output itself is read from the UTF-16 log.

This is not a special case for `du`. It also fixes Unicode text in module paths, `!analyze` output, string dumps, and other debugger commands. Systems with a single-byte code page continue to use the existing pipe-based output.

I tested the fix with real crash dumps, a live kernel target, and remote sessions using the 1252, 936, and 65001 code pages.

## Getting Started

Upgrade with:

```bash
pip install -U mcp-windbg
```

If you use the Claude Code plugin, update the plugin to pick up the new version.

The project is available on [GitHub](https://github.com/svnscha/mcp-windbg). If you notice any other commands behaving differently on a non-English Windows system, please [open an issue](https://github.com/svnscha/mcp-windbg/issues).