40161: Operation requires an identified client

The client had no established client ID, so an operation that requires one was refused.

What you should do

Authenticate the client with a client ID, or relax the namespace setting that requires one. A client gets an identifier by connecting with a token issued for a specific client ID, making it an identified client. Alternatively, change the namespace's settings in your app so it no longer requires identified clients.

Why it happens

An operation was attempted on a channel whose namespace requires identified clients, by a client that had no client ID. The identified namespace enforces this by default, and any namespace can be configured to.

What you'll see

The error is reported with code 40161 and HTTP status 401. The message is typically Access denied to channel: namespace <name> requires identified clients or operation not permitted as it requires an identified client.