# 40016: Invalid message name

Identifier: `invalid_message_name`



A message supplied a name that was invalid, so the message was rejected.

## What you should do

Set the message [`name`](https://ably.com/docs/channels/messages.md#message-properties) to a string, or leave it unset. Correct the value and republish.

## Why it happens

The `name` supplied on a message was not a string. The name is an optional label for the event, and when present it must be a string.

## What you'll see

The error is reported with code 40016 and HTTP status 400. The message is `Invalid message name`.