you will need to re-authorise the eReader with digital editions. best way I found was open editions on the PC then connect the ereader. It should ask you to autourise it. Once done just drag and drop the books (1 at a time) onto the ereader icon in digital editions and all should be o.k. Disconnect from the pc and then look for the books in the digital editions folder on the new menu that the update has added. They sould then open o.k.