How to prevent Dropbox files from being sync'd to both WD My Cloud device an laptop drive?

My Cloud OS 3 Personal & Network Attached Storage My Cloud
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What does this mean? What software are you using? What or which My Cloud model did you buy? Did you install any other WD software?

Officially there is no direct linkage between the single bay My Cloud and Dropbox without using a computer.

Unofficially there may be a way using Goodsync to link the My Cloud to Dropbox without going through a computer.