I just got a Seagate expansion external 500 gb hard drive. All I want is drop and drag to save files. Chat lines said this was possible. Easily. So I got the Seagate. When it first opened up, it asked if I wanted to use it as a Time Machine backup. Not really. I just want drop and drag file saving capability. Now, it just sits there. I cannot drop and drag. How to I enable it, or format it (I am not a techie) so that I can drop and drag?