Upgraded C# / ASP.NET MVC project from .NET 4.7.2 to .NET 8.0

Question

I have upgraded an ASP.NET MVC project, written in C# and running on .NET 4.7.2, to .NET 8.0.

I get this error:

The type or namespace name 'DirectoryServices' does not exist in the namespace 'System' (are you missing an assembly reference?)

I have tried to install System.ServiceModel.Primitive and it didn't work.

The old code uses

using System.Security.Principal;
using System.ServiceModel;