Identity Scaffolding to existing project is broken

Describe the bug

Attempting to scaffold the Identity views into an existing .NET 5 project which references v5.0.5 of the Identity libraries does not work. The tool down-grades the NuGet package references, then complains that there are build errors because the site references a lower version of the packages than a referenced class library.

To Reproduce

Using Visual Studio 2019 v16.9.4, create a new solution with two projects:

• A .NET 5.0 class library;
• An ASP.NET 5.0 site;

In the class library, reference Microsoft.AspNetCore.Identity.EntityFrameworkCore version 5.0.5, and Microsoft.EntityFrameworkCore version 5.0.5. Create a class derived from IdentityContext.

In the site, reference the class library, and reference Microsoft.AspNetCore.Identity.UI version 5.0.5. Configure identity to use the context from the class library.

Verify that the solution builds without errors.

Right-click on the site and select “Add -> New Scaffolded Item”. Walk through the steps to scaffold the Identity views, as described in the documentation, selecting the correct context from the drop-down list.

After a while, the operation fails with an error:

The Identity and EF Core references in the site have been down-graded to version 5.0.4, and the site now fails to build because the class library references a higher version!

Further technical details

.NET SDK (reflecting any global.json): Version: 5.0.202 Commit: db7cc87d51

Runtime Environment: OS Name: Windows OS Version: 10.0.19042 OS Platform: Windows RID: win10-x64 Base Path: C:\Program Files\dotnet\sdk\5.0.202\

Host (useful for support): Version: 5.0.5 Commit: 2f740adc14

Microsoft Visual Studio Professional 2019 Version 16.9.4 VisualStudio.16.Release/16.9.4+31205.134 Microsoft .NET Framework Version 4.8.04084 Installed Version: Professional

[flicwin]

Since 5.0.10 I’m unable to roll anything back because the first order of business when scaffolding Identity is to bring the corresponding packages up to date - which means every attempt to scaffold returns a rollback error. I have found an interim fix here which solved my issue. This article was written in February and people have been thanking the author all year. I hope it helps you too.

[flicwin]

Created a new Blazor Net Core Hosted application with default IdentityServer & EntityFramework packages Version=“5.0.9” and received the same critical error during a scaffolding attempt overriding all. I changed the packages down to 5.0.8 and ran the scaffold again which this time completed successfully. Microsoft Visual Studio Community 2019 Preview Version 16.11.0 Preview 2.0