I am an absaloute computer novice and have been trying to download ebooks from book sites that ive purchased using adobe digital editions which has authorised adobe id etc. The book downloads then I am given 2 options 1 open 2 view download so I select open. This is where the issue occurs its wanting to open the file in adobe reader not digital editions and I get this exact message "Adobe reader could not open (book).acsm because it is either not a supported file type or because the file has been damaged (for example it was sent as an email attachment and wasn't correctly decoded". This has happened with 2 purchases at 2 different book stores, I have done everything suggested, authorizing adobe id, installed digital editions 4.5, even changing computer default settings to accept acsm files. I would appreciate any help as I have books paid for stuck in the system. Kym from Melbourne.