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Could not load file or assembly 'Python.Runtime, Version=2.4.0.0...

See original GitHub issue

Environment

Pythonnet version: 2.4.00
Python version: 2.7.13
Operating System: Windows 7

Details

Describe what you were trying to get done.

I have used pip install git+https://github.com/pythonnet/pythonnet to install latest python net.

I’ve created a .NET visual studio 2015 project to make calls to Python. I reference the Python.Runtime.dll file in the project. When I let it get copied to the binary directory of my project calls to CPython work fine.

Now, I don’t want to bundle the DLL with my application. As I understand, different versions work with different versions of CPython. I would like to load Python.Runtime.dll from Lib\site-packages so I get version appropriate for version of Python installed on the system. I change properties of the PythonRuntime.dll reference to NOT copy the DLL to bin directory. Now I get the error:

An unhandled exception of type 'System.IO.FileNotFoundException' occurred in PyRunner.exe
Additional information: Could not load file or assembly 'Python.Runtime, Version=2.4.0.0, Culture=neutral, PublicKeyToken=null' or one of its dependencies. The system cannot find the file specified.

This minimal program causes the error.

using Python.Runtime;

namespace PyRunner
{
	class ErrorExample
	{
		static void Main(string[] args)
		{
			PythonEngine.Initialize();
		}
	}
}

I’ve tracked down other issues related to this but none seem to simply be that the DLL is not found.

When I try to install the assembly in the GAC I get

>gacutil /i Lib\site-packages\Python.Runtime.dll
Microsoft (R) .NET Global Assembly Cache Utility.  Version 4.0.30319.0
Copyright (c) Microsoft Corporation.  All rights reserved.

Failure adding assembly to the cache: Attempt to install an assembly without a strong name

Thanks