If you want to retain all your existing, automatic backups in Dropbox, move your existing 'Automatic Backups' folder to the new Dropbox directory you created in step 1 above.
You can create a folder within your Dropbox and place your Quicken Backup file in this location. Here are just a few options: Automatically put your Quicken Backup Files on Dropbox You can use Dropbox as a backup tool in a number of ways. All files in your Dropbox folder are automatically backed up to Dropbox every time a file is added or changed. After you've set up Dropbox on your computer, you can back up any file, (including your Quicken backups), by placing it in the Dropbox folder.