C# .NET Framework (WinHttpHandler) client vs. Python3 server, unsupported protocol issue

[p1x31]

Please reopen #29659 I'm getting the same error but with windows 11

What version of gRPC and what language are you using?

python3-grpcio 1.62.1, Grpc.Net.Client 2.62.0 in C# .NET Framework 4.8.1

What operating system (Linux, Windows,...) and version?

Windows 11 Pro 23H2

What runtime / compiler are you using (e.g. python version or version of gcc)

Python 3.10.6

What did you do?

Please provide either 1) A unit test for reproducing the bug or 2) Specific steps for us to follow to reproduce the bug. If there’s not enough information to debug the problem, gRPC team may close the issue at their discretion. You’re welcome to re-open the issue once you have a reproduction.

I implemented a simple gRPC client in C# .NET Framework (WinHttpHandler) and a gRPC server in Python3 (grpcio) for testing.

What did you expect to see?

A returned string value from my gRPC method call.

What did you see instead?

WinHttpException: Error 12029

Make sure you include information that can help us debug (full error message, exception listing, stack trace, logs).

See TROUBLESHOOTING.md for how to diagnose problems better.

Anything else we should know about your project / environment?

please refer to grpc/grpc-dotnet#2439

[p1x31]

I've come up with a solution here