I recently borrowed an ebook from my local library and transferred it to my Kobo Clara manually via ADE (because Kobo doesn't have the book so I cannot link that library loan automatically) . However, a message popped up saying that my ereader is not authorised and cannot be read because of the DRM file to that ebook. I contacted Kobo themselves, and they guided me through de-authorising both my computer and Kobo, then authorising them again. I was even instructed to do a factory reset. The message still pops up despite everything. I contacted Adobe, they told me to post my question here, so here I am. Does anyone have any idea?