Device not added to ADE

I have followed the steps for connecting my kobo aura to ADE, but when I connect my kobo to the program to authorize the device there are no devices listed on the left of the page.  My kobo shows that it is not authorized and I can't download any books from my library.  I would really like some help as I got the kobo because I am going to be travelling for the next four months and I liked the convenience of bringing the library with me.  Please help!