I had purchased a 1TB My Book Essential and attempted to use this on my system for just over a week. This is the third backup drive I have installed and the first from WD. This was also the first that has given me any problems. I eventually returned this device, along with three others I purchased for family members for the holidays, due to the problems from my device and not wanting to have to support the three others once they were installed. I followed all the necessary steps in troubleshooting and do this for a living. There were six areas that lead me to return this device and pick up new drives from a different company. I am running on Windows 7.
Speed - the first problem I noticed was a very slow scanning and transfer rate on the drive. I assumed it was the USB port or cable, but running other drives on this same cable/port provided normal operating rates using USB 2.0. Trying to back up even 1 GB was taking over six hours.
Software Updates - The firmware and then subsequent WD SmartWare software updates were not very intuitive and seemed to be successfully installed. In hindsight, I probably should have tried to rollback these updates as they could have been the source of my problems, but the drive was slow out of the box.
Retrieval - It would take the drive about 45 minutes to categorize file types for retrieval, but I also noticed that email files from Office 2007 would not be included in the backup from default locations. I was wondering what other files were missing from the backup, but trying to dig through the categorization and retrieval settings was nearly impossible. The first retrieval I attempted failed with the BSoD after nearly 90 minutes and I was only trying to test this with about 50 files and at about 350MB. More on the BSoD later.
Permissions - After a few additional attempts to retrieve files, the files that were brought back to the PC had permission problems. I was running the retrieval (and original backup) as the same user with admin permissions. For some reason the files appear to have permission changes going from my PC to the WD My Book and back. I could not open the files without manipulating permissions through Windows.
Crashes My PC - The most obvious problem was my PC crashing with the BSoD at least twice a day. At first, I assumed there was a PC hardware problem and stepped through all the normal diagnostics. Even had HP Support on the phone with me. After system restores and even going so far as to restore the PC to the original factory settings over the course of a week, the common denominator was the WD My Book creating the crashes. I was fortunate enough to have all my files backed up on two other external drives that were not WD devices, so the restore wasn't much of a deal, but I'm doubting most people have this luck. After removing the WD My Book and eventually uninstalling the software my PC has been magically healed.
Uninstall Doesn't Remove all Software and Settings - Even after realizing this WD My Book Essential 1TB wasn't for me and going through the uninstall procedures, I realized there were still several traces of the software and virtual CD map included on my PC. I was able to find solutions to these in other forum posts and searching on the web.
I was hoping this external drive would have been a good product, but it failed on too many levels. It obviously could have been a combination of factors on my PC, a bad device (2 of them in the same batch?), or anything else. I hope you have better luck with it - or save your receipt.