I'm not saying that this is in anyway "best practices," but I'm in a peculiar situation where I need to restrict users from starting a "retired" Ensemble Production in a namespace that's been renamed. It's still an "Ensemble-activated" namespace; we need to keep it available for Ensemble Message Viewer access ... fortunately, only for a little while. It's a bit of a hack ... Open the Production class in Studio and add the following classmethod: ClassMethod OnStart() As %Status { Return $system.Status.Error(5001,"THIS PRODUCTION IS DISABLED.") } A Production won't start if its OnStart() callback returns an error. And that's exactly what **this** OnStart() method does![laugh](https://community.intersystems.com/sites/all/libraries/ckeditor/plugins/smiley/images/teeth_smile.png "laugh") Of course, if there are better ways to accomplish the same thing, I'm all ears!