While viewing thumbnails of image files in a folder on my laptop this morning, the files quickly deleted before my eyes. This happened for several consecutive folders, but was limited to only a certain set of consecutive subfolders. No image files of those series were deleted outside of that higher level folder, yet every image file in them was deleted. A Norton Antivirus scan with updated virus definitions didn't find any virus. A complete search of my computer does not turn up the missing files anywhere, even in the Recycle bin. I was not online when the files disappeared. The only unusual things happening that day were that I accessed a foreign website via FTP, I did a wipe on my Recycle bin earlier in the day, and my boss is getting paranoid about having unused computers around here and about tracking e-mail, though my computer should have been inaccessible to everyone for the past few days. Any ideas as to what is going on?

Addenda: I tried deleting text files manually, and those go into the Recycle bin as expected. I viewed images in other folders but those have not disappeared. The problem seems to be limited to a specific range of folders containing only image files, and maybe only for a limited time this morning. Could my hard drive be going bad?