When you plug your reader cable into the usb port, a window will open up with two folders inside just as if you had plugged in a usb drive. One is named database and the other is named digital editions. Click on the database folder and in the next window; three more folders open up. Click on the media folder, and the next folder you will see is called books. Open it up and there are your ebooks, you can select them and copy them to another folder. Note: I have not downloaded any ebooks from the sony store. I used Calibre (a very good conversion program) to make my own ebooks. That is the content I have in my ebook library. I do not know if this will work for purchased books. I hope that this will help you recover the books from your ereader. This is the path to the books in my ereader when the folder comes up.
If the window does not open up go to my computer, and click on the ebook reader icon in there, and follow the steps above.