Cannot load plugin in Rhino8 .Net7


When trying to load a plugin made with .net 7 it fails with this error (.Net7 runtime is installed on the machine):

System.IO.FileNotFoundException: Could not load file or assembly 'System.Runtime, Version=, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified.
File name: 'System.Runtime, Version=, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
   at System.Reflection.RuntimeAssembly.GetExportedTypes(RuntimeAssembly assembly, ObjectHandleOnStack retTypes)
   at System.Reflection.RuntimeAssembly.GetExportedTypes()
   at Rhino.PlugIns.PlugIn.CreateFromAssembly(Assembly pluginAssembly, Boolean displayDebugInfo, Boolean useRhinoDotNet)

Assembly manager loaded from:  C:\Windows\Microsoft.NET\Framework64\v4.0.30319\clr.dll
Running under executable  C:\Program Files\Rhino 8\System\Rhino.exe
--- A detailed error log follows. 

=== Pre-bind state information ===
LOG: DisplayName = System.Runtime, Version=, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a
LOG: Appbase = file:///C:/Program Files/Rhino 8/System/
LOG: Initial PrivatePath = NULL
Calling assembly : S3D_Eternity, Version=, Culture=neutral, PublicKeyToken=null.
LOG: This bind starts in LoadFrom load context.
WRN: Native image will not be probed in LoadFrom context. Native image will only be probed in default load context, like with Assembly.Load().
LOG: Using application configuration file: C:\Program Files\Rhino 8\System\Rhino.exe.Config
LOG: Using host configuration file: 
LOG: Using machine configuration file from C:\Windows\Microsoft.NET\Framework64\v4.0.30319\config\machine.config.
LOG: Post-policy reference: System.Runtime, Version=, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a
LOG: The same bind was seen before, and was failed with hr = 0x80070002.

Unable to load S3D_Eternity.rhp plug-in: initialization failed.

To load a .net 7 plugin you will need to run the SetDotNetRuntime command and choose NetCore. I think that the above shows it is trying to load from .net 4

But Rhino8 is .net7 (net core) by default. Why i need to change it?

@Smart3D_net Rhino 8 is indeed .Net Core by default:

Some Rhino 7 plugins need the full .Net Framework to run, these can be loaded in Rhino 8 by making Rhino 8 use .Net Framework using the _SetDotNetRuntime command.

A better long-term solution that will let you have all the benefits of the latest .Net Core versions is to update and recompile your plugin so it targets .Net Core. There is more info on how to do that on this page: