All external WD Passport series hard drives of all sizes come with what is known as WD SmartWare. It is actually somewhat useful, providing access to the drive's hardware based encryption (the drive itself has a firmware to handle the encryption/decryption). It also has neato backup features.
Now, I had previously mentioned WD SmartWare because it had a medium size memory leak that would grow over time to be quite problematic, being a resident application. I am glad to say WD fixed this memory leak. I can only imagine some universe where it was because they read this blog ;). Who knows, perhaps they have a Google Alert set for their software as I do for mine.
Problem: The backup features are designed for that Average Joe that theoretically exists somewhere, but never quite does. The first thing it does, even if *completely* disabled and non-used, is launch WDFME.EXE in the background which scans all your drives for content and categorizes it by type (e.g. Music, Photos, Video, Documents, etc..). It keeps doing this persistently, dragging down system performance so long as it is running.
The simple solution? Don't install WD SmartWare and instead use the Unlock.exe provided on the drives. Otherwise, use Process Lasso to make sure WDFME.EXE is terminated every time it is run. The WD Smartware software continues to otherwise operate normally, and maybe the backup even works (maybe, maybe not). Windows Backup is likely a better thing to use as a backup mechanism, though it too lacks much control, which is why I use an old fashioned robocopy ;).