File Location Has Changed

Can anyone help?

I've not used rekordbox for a few months now but before I had music d/led from Beatport onto my Desktop (C Drive) went into Rekordbox and d/led them into it and it would automatically put them in my portable HDD ( D drive) CONTENTS folder.

Now when I add them to rekordbox from the desktop it keeps the same location C:/Desktop. Obviously when I take out my HDD and plug it into the CDJ it cant find the tracks.

How can I change it back so when I d/l a music track from my desktop to rekordbox, it will automatically put it in my D:/CONTENTS folder?

I dont want to be manually draging and dropping files into folders and re-assigning them.