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Frustration! I am having trouble authorizing my Kobo e-reader for Adobe Digital Editions. As a result, I am unable to drag and drop epub files from my computer to my Kobo device. I have an Adobe ID, but when I attempt to complete the authorization process for my device, I receive a message stating "You can only authorize this computer with an Adobe ID that hasn't been previously used to authorize any other computer or device, Please try again."   I am not aware that I previously authorized and other computer or device. Any suggestions?