MCP Server not launching

[RajivJJ]

I have tried severeal things Still not working Claude has listed this problem. I also tried chagpt cant get it to work. I not very technical Would really appreciate the help::

Main Issues Identified

Missing pywintypes module (early attempts with regular Python)
Missing mcp module (when using hython - Houdini's Python)
Module conflicts between Houdini's Python environment and the virtual environment

Root Cause
The core problem is that when you use hython.exe (Houdini's Python interpreter), it's trying to import MCP packages from your virtual environment (.venv), but hython has its own Python environment with forced site-packages that interfere with standard imports. The line in your logs shows:
'C:/PROGRA1/SIDEEF1/HOUDIN~1.278/python311/lib/site-packages-forced'
This "forced" site-packages directory takes precedence and breaks the normal import mechanism.
Solutions
Option 1: Install MCP directly in Houdini's Python (Recommended)
Instead of using a virtual environment, install the MCP packages directly into Houdini's Python:
bash"C:\Program Files\Side Effects Software\Houdini 20.5.278\bin\hython.exe" -m pip install mcp fastmcp pywin32
Then modify your Claude Desktop config to run hython directly:
json{
"houdini": {
"command": "C:/Program Files/Side Effects Software/Houdini 20.5.278/bin/hython.exe",
"args": ["C:/Users/josep/Documents/houdini20.5/scripts/python/houdinimcp/houdini_mcp_server.py"]
}
}
Option 2: Use a wrapper script that properly isolates environments
Create a launcher script that doesn't mix Houdini's Python with the virtual environment. This requires not using hython at all, but instead having Houdini run as a separate process that your MCP server communicates with via RPC/socket connection (like your earlier bridge attempts).
Option 3: Remove the sys.path manipulation
In your houdini_mcp_server.py, the lines that add the venv to sys.path are causing conflicts with hython. Either:

Remove those lines entirely if using Option 1
Or ensure they're only added when NOT running under hython

Immediate Next Steps
Try Option 1 first:

Open a command prompt as administrator
Run: "C:\Program Files\Side Effects Software\Houdini 20.5.278\bin\hython.exe" -m pip install --upgrade pip
Run: "C:\Program Files\Side Effects Software\Houdini 20.5.278\bin\hython.exe" -m pip install mcp fastmcp pywin32
Update your Claude Desktop config to use hython directly without uv run
Restart Claude Desktop

Let me know if you'd like me to help you implement any of these solutions in more detail.