"error": "invalid_scope" when trying to create an Adobe ID to use with ADE

Hello. My company recently launched eBooks with DRM on our ecommerce site. Customers download and install Adobe Digital Editions in order to fulfill the .acsm files that are generated (we are a Magento site that uses a plugin called Edition Guard). We had a customer today that tried to both sign in to her account as well as create a new adobe account, and each time was given the error message {"error":"invalid_scope"}. I just tested and got the same error. I have seen this before when we were implementing all of this and it just sort of seemed to resolve itself at some point. Really I'd just like to get some understanding as to what is going on and what we can convey to our customers in case this happens. Here is where we are directing customers to log in or create an adobe id in order to authorize their computer using ADE .