Hi: I have or had multiple files and documents backed up on several computers and hard drives. They are in folders, in subfolders, in subfolders. Over the years they've been copied from computer to computer and through various external drives. Recently some documents have vanished from D: where I usually store them 1st before copying to a USB HD. Some folders are missing. More document folders are totally empty. Many contain only thumb.db files. For example, one folder that was 70 GB when created is now 8.4 MB and has a lesser number of documents. Even more of the vanishing documents have vanished from my current USB hard drives or the internal secondary hard drive on both Windows 7 and Windows 8.1 computer. Now I have discovered that a folder (Audacity) which resides on the desktop as 19.5 KB contains only a thumb.db file. Audacity can be copied to my hard drive folder and that there it contains 1.57 GB with 5 separate entities. Could this desk top-document folder disparity provide a clue as to why I have the missing documents. I have ensured ownership of these files and customized them to “optimized for documents”. No folders are hidden. I will greatly appreciate any comments.