I was just wondering if, when using the WD My Book, I can remove files from my C: drive and still have them backed up on my WD My Book drive?
If you do that and the external has a problem you’ve lost your files. Never trust important data to just one physical HD internal or external. If you look here you see numeorus posts from people who did what you want and are desparately trying to get their data back after a disaster.