Dropbox taking up storage on physical devices

Dropbox can fill up your hard drive because it stores local copies of your files for synchronization. To manage this, you can use Dropbox's Selective Sync feature to choose which folders to keep locally, or you can make files online-only, meaning they're only stored in your Dropbox account and downloaded when needed.

I found when I took the selective sync off it did start removing the files from the computer but didn't really free up space.

So with the selective sync off I found a folder under the Dropbox folder that said old files. It has a bunch of random letter file names, by deleting those it freed up hard-drive

The user should only use Dropbox online or their storage will fill back up