Are there any logs written out during a Houdini Engine session in Unreal?
During these work-from-home days I have artists that are getting sporadic, hard-to-repro errors like

LogHoudiniEngine: Error: Failed to restart the Houdini Engine session

We have a VPN system to pick up licenses which seems stable enough. So looking for more info on why the session couldn't be restarted.
Thanks.

We generally write as much logs/errors/warnings as we can in the UE log files.
After the restart fails, you could try and see if “fetch cook log” displays more details, as it also fetch the error descriptions for the latest HAPI error.

Version 1 of the plugin still has a bug that sometimes forces you to restart the session twice to get a proper connexion to HARS.

You can try to change the session type (named pipe / tcp) and see if this helps, also, if using TCP, you'll want to make sure that the port used is free/open.

What versions of the Houdini / the plugin / UE4 are you using ?

— edit: You could also try and see if increasing the timeout for the session helps, default timeout is set to 3s.
you can do this by changing the automatic session timeout value in the project settings (the value is in ms)

Thanks for the ideas @dpernuit. That might be useful.
We are on UE 4.24.1 running plugin built against Houdini 18.0.391 and engine 3.3.2