Is it possible to configure the Runspace for Connections into my Process with Enter-PsHostProcess? #25583

Hi! From what you describe, the main limitation seems to be the distinction between attaching to an existing PowerShell host process and creating a new runspace with a custom InitialSessionState.

Enter-PSHostProcess primarily provides process attachment and runspace debugging capabilities. Although it supports connecting through a named pipe, it does not expose an option to supply a custom InitialSessionState for the runspace created for that connection.

There is a public SDK type worth looking into:

System.Management.Automation.Remoting.RemoteSessionNamedPipeServer

It exposes CreateCustomNamedPipeServer(string). However, the documented API does not appear to provide a way to inject a custom InitialSessionState or associate incoming connections with your existing application runspaces.

For your scenario, I would consider two approaches:

1. A custom IPC bridge into your existing runspaces

Keep runspace creation and configuration inside your C# application, using RunspaceFactory.CreateRunspace(initialSessionState).

Expose an authenticated IPC endpoint that forwards requests to your application, where commands are dispatched through the existing PowerShell SDK infrastructure.

This would let you preserve your custom cmdlets, variables, and application state.

The trade-off is that this is not automatically compatible with Enter-PSSession or Enter-PSHostProcess. You would need a client integration layer.

2. A custom PowerShell remoting endpoint

If native PowerShell remoting compatibility is essential, you would need a host or endpoint implementation that creates sessions using your application's configuration.

Windows WSMan session configurations support custom session environments, but they are not directly applicable to the named-pipe connection established by Enter-PSHostProcess.

One additional consideration: if your PSVariable implementations reference live objects in the C# process, hosting a separate PowerShell process may not preserve those references. Keeping execution inside the original process is likely important.

So, to answer your question directly: I don't know of a supported way to provide a custom InitialSessionState directly to incoming Enter-PSHostProcess connections. A custom IPC bridge appears to be the more practical route if reusing your existing application runspaces is the priority.

References:

• [Enter-PSHostProcess documentation](https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.core/enter-pshostprocess)
• [RemoteSessionNamedPipeServer API](https://learn.microsoft.com/en-us/dotnet/api/system.management.automation.remoting.remotesessionnamedpipeserver)
• [Creating an InitialSessionState](https://learn.microsoft.com/en-us/powershell/scripting/developer/hosting/creating-an-initialsessionstate)