Although it's listed as a Supported ereader, ADE seems to have trouble
recognizing the T1. For practical purposes, try using the SONY Reader
Library software.... Sorry!
The back door to go from ADE to Sony Reader PSR-T1
Download book to Digital Editions, close it. Go to My Documents, to My Digital Editions folder--open it. Pick the file of the book you want on your Reader and right click on it--go to open with--choose Reader for PC. The book should open in Reader for PC (you will need to log in)-- click the back arrow. You should be on the home page and the book should show in My Library. Transfer from Reader for PC to the Reader as usual.
I hope this will help you.