How to sync newly installed Adobe DE (with recently purchased eProducts) to my Adobe ID

Hi

I have just purchased some eBooks and downloaded to a newly installed Adobe DE.  I am trying to sync it with my existing Adobe ID account.

However, I don't seem to be able to do it and the error message is as follows:

"You can only authorize this computer with an Adobe ID that hasn't been previously used to authorize any other computer or mobile devices.  Please try again."

I do not want to set up another Adobe ID but to use the same ID to sync all the products I have purchased.  Pls help.  Thanks.