Claude Desktop in Windows 10 was unable to get MCP working in Claude Pro

[davidacollins]

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• I have checked that this question would not be more appropriate as an issue in a specific repository
• I have searched existing discussions and documentation for answers

Question Category

• Protocol Specification
• SDK Usage
• Server Implementation
• General Implementation
• Documentation
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Your Question

Summary provided by Claude:

Environment

• Windows 10 (Version 10.0.19045.6466)
• Claude Desktop for Windows, Version 1.9255.0
• Claude Pro account
• Node.js v24.16.0 (installed fresh during troubleshooting)
• npm installed globally via npm install -g npm

Goal
Set up the MCP Filesystem Server in Claude Desktop to give Claude read/write access to a local project folder at:
C:\Users\User\Documents\Monith Developments\Value_Stable_Title

What We Did

1. Created %APPDATA%\Claude\ folder manually (it didn't exist)
2. Created claude_desktop_config.json in that folder
3. Confirmed Node.js was installed but not in PATH — fixed by adding C:\Program Files\nodejs\ to System Environment Variables (it was actually already there; the fix was reopening Command Prompt)
4. Confirmed node --version returns v24.16.0
5. Confirmed npx -y @modelcontextprotocol/server-filesystem "C:\Users\User\Documents\Monith Developments\Value_Stable_Title" runs successfully and returns: Secure MCP Filesystem Server running on stdio
6. Confirmed the package is cached at: C:\Users\User\AppData\Local\npm-cache_npx\a3241bba59c344f5\node_modules@modelcontextprotocol\server-filesystem\dist\index.js
7. Confirmed running node.exe directly against the cached index.js also returns Secure MCP Filesystem Server running on stdio

Configs Tried (all failed to produce hammer icon)
Config 1 — Standard:

{
  "mcpServers": {
    "filesystem": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-filesystem",
        "C:\\Users\\User\\Documents\\Monith Developments\\Value_Stable_Title"]
    }
  }
}

Config 2 — Full path to npx.cmd:

{
  "mcpServers": {
    "filesystem": {
      "command": "C:\\Program Files\\nodejs\\npx.cmd",
      "args": ["-y", "@modelcontextprotocol/server-filesystem",
        "C:\\Users\\User\\Documents\\Monith Developments\\Value_Stable_Title"]
    }
  }
}

Config 3 — Using cmd /c wrapper:

  "mcpServers": {
    "filesystem": {
      "command": "cmd",
      "args": ["/c", "npx", "-y", "@modelcontextprotocol/server-filesystem",
        "C:\\Users\\User\\Documents\\Monith Developments\\Value_Stable_Title"]
    }
  }
}```

Config 4 — Direct node.exe with full path to cached package:

{
"mcpServers": {
"filesystem": {
"command": "C:\Program Files\nodejs\node.exe",
"args": [
"C:\Users\User\AppData\Local\npm-cache\_npx\a3241bba59c344f5\node_modules\@modelcontextprotocol\server-filesystem\dist\index.js",
"C:\Users\User\Documents\Monith Developments\Value_Stable_Title"]
}
}
}

Config 5 — With explicit APPDATA env variable:

{
"mcpServers": {
"filesystem": {
"command": "npx",
"args": ["-y", "@modelcontextprotocol/server-filesystem",
"C:\Users\User\Documents\Monith Developments\Value_Stable_Title"],
"env": {
"APPDATA": "C:\Users\User\AppData\Roaming\"
}
}
}
}

**Symptoms**
- No hammer/tools icon appears in Claude Desktop chat input after any restart
- No logs folder is ever created in %APPDATA%\Claude\
- No Developer tab visible in Claude Desktop Settings
- Asking Claude to list files defaults to Google Drive instead of local filesystem
- All manual command-line tests of the server succeed without errors

**Key Observation**
The complete absence of a logs folder suggests Claude Desktop is not attempting to launch the MCP server at all, despite the config file being present and valid at C:\Users\User\AppData\Roaming\Claude\claude_desktop_config.json

[isheng-eqi]

The key symptom is that no logs folder is ever created. This means Claude Desktop is not even attempting to read your config file. Here are the Windows-specific causes and fixes.

Most likely cause: Claude Desktop on Windows uses a different config path

On Windows, newer versions of Claude Desktop may use a different config location than %APPDATA%\Claude\. This is a known source of confusion.

Check these paths (in order):

1. %APPDATA%\Claude\claude_desktop_config.json
   → typically C:\Users\<User>\AppData\Roaming\Claude\claude_desktop_config.json

2. %LOCALAPPDATA%\AnthropicClaude\claude_desktop_config.json
   → try this if the first one does not work. Some Windows builds use this path.

3. %USERPROFILE%\.claude.json
   → This is Claude Code's config format, but some Desktop versions also check it.

The fact that there are no logs at all strongly suggests the config file is in the wrong location. When Claude Desktop finds the config file but fails to launch the server, it still creates a logs folder. Zero logs = config not found.

Quick test to find the actual path

Create a deliberately broken config to confirm which path Claude reads:

{"this_is_broken": true

Place it in each candidate location one at a time, restart Claude Desktop, and check if a logs folder appears. If logs appear with an error, you have found the correct path. Then replace with the valid config.

Second likely cause: JSON escaping issues in your path

Your path C:\\Users\\User\\Documents\\Monith Developments\\Value_Stable_Title has an underscore that should be fine, but the original had \\_Stable\\_Title — check that you are not accidentally escaping anything. In JSON, backslashes in Windows paths need to be doubled:

{
  "mcpServers": {
    "filesystem": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-filesystem",
        "C:\\Users\\User\\Documents\\Monith Developments\\Value\\_Stable\\_Title"
      ]
    }
  }
}

Also: spaces in path segments (like Monith Developments) can cause issues because npx splits arguments on spaces. Try wrapping the path:

"args": [
  "-y",
  "@modelcontextprotocol/server-filesystem",
  "\"C:\\Users\\User\\Documents\\Monith Developments\\Value\\_Stable\\_Title\""
]

Or better, use a path without spaces as a test.

Third: No Developer tab on Windows 10

The missing Developer tab is a separate issue — it is a known limitation on some Claude Desktop Windows builds. It does not affect MCP functionality; it just means you cannot see debug logs in the UI. The hammer icon should still appear if MCP is configured correctly.

Recommended test config (minimal, no spaces)

1. Create a test folder: C:\test_mcp
2. Use this minimal config:

{
  "mcpServers": {
    "filesystem": {
      "command": "npx.cmd",
      "args": [
        "-y",
        "@modelcontextprotocol/server-filesystem",
        "C:\\test_mcp"
      ]
    }
  }
}

3. Place the file at BOTH candidate locations:

   • %APPDATA%\Claude\claude_desktop_config.json
   • %LOCALAPPDATA%\AnthropicClaude\claude_desktop_config.json

4. Fully quit Claude Desktop (check Task Manager for lingering processes)

5. Restart and look for the hammer icon

If neither path works, run Claude Desktop from Command Prompt to see startup errors:

"C:\Users\<User>\AppData\Local\Programs\Claude Desktop\Claude Desktop.exe"

Watch the console output for config-related errors.