WD My Book Essential 3tb "loses files" but retains folders?

I am using a Dell 5758 Laptop, W7 with 629GB of free space. I use the My Book Essential as back-up as well as a “working hard-drive” I download images into folders on the My Book and edit them in Photoshop 6, which is on the ‘C’ drive of the computer. My intention is to keep the ‘C’ drive with as much free space as possible. I have encountered lots of problems with the Adobe Bridge browser function - most times having to re-boot the computer before it recognizes the files on My Book. However today, I went to the folder on the My Book with Internet Explorer and was told that Windows Image Preview “could not find the file, it has been deleted or moved”. The folders are still there, correct names and everything, but there are no files in them.
I went into WD Smartware with the intention of ‘retrieving’ the backed up files (??) - found that that would not be possible - when I went back into the My Book I found the files came up both in W Explorer and Adobe Bridge (the way they’re supposed to) but now after copying some of the folders into a folder on my Desktop…the files have disappeared again…??
I’m wondering if it’s the computer, the My Book or the software causing the problem?
Any advice/assistance would be much appreciated.

Hi, does the drive still shows the use size? Have you tried enabling “Show Hidden Files and Folders” in the folder options?

Hi,
Yes, usually the drive does show the use size and also the actual folders (I have only image files on this drive) but when I open the folders - nothing - “This folder is empty”! But today when I first fired up the computer the My Book was recognized, but when I opened it it said “This folder is empty”! I restarted the computer and it then recognized it. I have unplugged the USB cable and re-plugged it and sometimes that will allow the files to be seen and opened, sometimes not. When I ‘restart’ the computer the drive is sometimes not recognized at all - sometimes it is! I always enable “Show Hidden Files and Folders”
Yesterday, with Smart Ware open, I saw that the drive which is set to back-up continuously
had not been doing so. I opened the Back-up tab and watched - it would back up about 5-6GB (of about 150GB) and then the My Book (target) would just disappear - even from Smart Ware! It’s baffling and frustrating to say the least!!
Thanks for responding,
Mike