Question: I have created a MC application (Component Type: API Application) so I can insert Subscribers into a Journey using API event.

Here is the scope
[![enter image description here](https://i.stack.imgur.com/FV5jQ.png)](https://i.stack.imgur.com/FV5jQ.png)

So I am stuck at the first hurdle, which is trying to authenticate. On the app detail page it provides "Authentication Base URI" which I have used to send my authentication request with the `clientID` and `clientSecret` inside the payload, however the server responds with "596 Service Not Found". 

I'm not sure what I'm doing wrong, I've noticed the app status is "In Development", I'm not sure if this has something to do with it but I cant see how to publish it.

My payload looks like this...

```
curl -X POST \
  https://mcgg0286b-adfdgrttrtrhhfgh.auth.marketingcloudapis.com \
  -H 'Content-Type: application/json' \
  -H 'cache-control: no-cache' \
  -d '{
    "clientId": "asfwerwer12323",
    "clientSecret": "asdfasf32432432"
}

```

Answer: 
So it turns out I've only hit the domain but not the correct resource.

I appended `/v2/token` to the URL and used parameters set out in this [page](https://developer.salesforce.com/docs/atlas.en-us.mc-app-development.meta/mc-app-development/access-token-s2s.htm).
Authentication and Triggered Send API are different. I was getting the same issue and after correcting i was able to resolve it. Please see the URLs below:

Auth URL =https://<>.auth.marketingcloudapis.com/v2/token

Triggered Send URL=https://<>.rest.marketingcloudapis.com/messaging/v1/messageDefinitionSends/key:xxxxx/send