Merging Folders

When dragging folders to the device, why can’t you merge folders?  I have hundreds of folders that I need to update frequently and the operation stops and states “Folder Already Exists”.  Is WD still not in the 21st century or is it a settings issue on my part?

That’s nothing at all to do with WD, it’s entirely your OS which controls that kind of thing (and you don’t say which one you’re using). But it’s a standard warning/notification, and if you accept it then the content of the folder you’re moving will be merged into the one already there.