In the above link it states "This element contains the customer's API username. A customer who uses the API creates a special user in ExactTarget that the API uses to log in. This user's password does not expire."
Is this API user the same user with credentials I use to log in with?
I have gone here: https://mc.s6.exacttarget.com/cloud/#app/Cloud%20Preferences
And the preferences state that the user I'm trying to login with is an API user but when I try to use the Soap API using the credentials I get this error: "Security requirements are not satisfied because the security header is not present in the incoming message."