When using Eloqua Cloud Apps, it is important to remember that the Eloqua credentials stored within your apps will need to be kept up to date. When your Eloqua credentials expire, and you change them within Eloqua, they will need to also be changed on cloudconnectors.eloqua.com.
Doing this is a quick and easy process, as you need only change them in one place, and it will cascade across all apps that use that set of credentials.
Here is what you will need to do:
Note: When your credentials expire, you should receive a notification email from cloudconnectors.eloqua.com letting you know.
Here is a brief video of how to do this http://screencast.com/t/X5cOgMgW6u0