Moving this discussion to the Adobe Digital Editions forum.
AphonseDaudet are you receiving a specific error message which is prompting you to post to the Adobe forums? If not then your question would probably be best answered by Bluefire. You can find a support page on this topic at http://www.bluefirereader.com/using-library-books.html.
As Jeff says, probably best to see if you can get help from Overdrive.
But you've probably already been to http://omc.overdrive.com/ , and they don't seem to have much help or a forum.
Bluefire that Jeff mentions is actually a different product than Overdrive that does much of the same job.
(Bluefire is what I use on iPad and it also works on Android).
On the whole I think Bluefire is better than Overdrive, and there have been quite a few cases of people having problems authorizing Overdrive.
Thanks Sjpt. Not an Adobe recommendation but I use Bluefire reader as well.
Overdrive's main advantage is that they can activate directly on the device which could be handy to some users. A lot of the public library systems in the U.S. also partner with Overdrive to provide their eBook hosting.
Thanks much for the assistance!
Sent from my iPhone
Jeff, I'm pretty sure I activated Bluefire directly on my iPad. Quite a time ago now, so I may have remembered wrong.
Overdrive partner with most of the UK public libraries for DRM loans.
I also only just realized Bluefire can download the .epub from the .acsm file, so no need for ADE at all.
I don't usually use my iPad for ebooks (much too heavy), so hadn't really used Bluefire that much.
I still need ADE to get the .epub so I can download it to the (Sony) eReader.
Anyway, it looks as if original poster is happy