Angular/SignalR Error: Failed to complete negotiation with the server

Question

Using SignalR for my server and Angular for my client... When I run my client I receive these errors:

zone.js:2969 OPTIONS https://localhost:27967/chat/negot         


        

Answer 1

I waste almost two days for this and finally figured out,

When this error occurs?

• When you upgrade your existing SignalR server project to .Net Core but do not upgrade the client
• When you create the SignalR server using .Net core but you use traditional .Net framework for the client

Why this error occurs?

• The error occurs because new SignalR does not allow you to use old server & new client or new server & old client

• It means if you create the SignalR server using .Net core then you must create the client using .Net Core

This was the issue in my case.