I am having the exact same problem. Have you found an answer anywhere else?
Which version of Digital Editions are you using?
Another post ( http://forums.adobe.com/thread/1120519?tstart=0 ) found that older Digital Editions did not recognize the Kobo Glo,
but that the latest v2.0 did.
However, they still could not register their Kobo. Maybe you will be luckier.
No I have not. I have been to Kobo online support and they could not help me. Thank goodness I have a Kindle!!!@
I am using version 2 but still no success. I purchased a book from Kobo yesterday and it appears in my Kobo desktop but not on my Kobo itself.
I have finally found a solution and a very simple one - with the assistance of C alibre - not Kobo support.
It was as simple as plugging my Kobo Glo directly into the computer, and not into a hub. As soon as I did that simple move, everything was fine! This is apparently a problem with Kobo and I found the answer with Calibre's support page. Pretty pathetic for Kobo support!
Hope it works for you as well Natasha!
Sorry for not responding earlier - I have been felled by the flu and have been in bed since posting my issue on Christmas morning. I did get it figured out with installing the newer version of Digital Editions. Thanks for your help! I have to say, I am relatively computer savvy and am disappointed by how un-user-friendly it is to get a book from the library onto my Kobo! Now that I have it figured out, I'll keep doing it, and am really glad that Kobo allows it (unlike the Kindle) but would like to see it be as easy as it is to buy something from Kobo online. In any case - KoboGlo has kept me in good company over the past few days. Best present ever!