Was the ebook in question a purchased title or a "free download" from the default ebooks in your Online Bookshelf (aka ETI Server)?
It could be that that ebook was secured (with DRM) to a "User ID" that is different from the User ID of your "transferred" device.
If your ebooks were purchased from
www.ebookwise.com, any ebook that was secured would have been encrypted to your eBookwise 1150's internal serial number as well as your User ID and thus would only be allowed to be read on that device. If you change your User ID, you should be able to transfer your previous
www.ebookwise.com purchases by contacting customer support and explaining your situation.
They will adjust (once) your Online Bookshelf to be tied to your new User ID so that your purchases can still be read (as long as you've kept your
www.ebookwise.com Login ID).