Trying to migrate from ASP.NET Core 3.1 to 5.0 using this guide provided by Microsoft.
Installed SDK 5.0.100-rc.1 with runtimes. Updated project as guide says and sti
I faced the same issue and asked Microsoft about that under this post: https://github.com/dotnet/aspnetcore/issues/27738
You need to update your projects to use below SDK's;
Client - Microsoft.NET.Sdk.BlazorWebAssembly Server - Microsoft.NET.Sdk.Web Shared - Microsoft.NET.Sdk