First create your Dropbox account and create a new app (https://www.dropbox.com/developers/apps).
After successful creation of account you will receive `app_key`, `app_secret` and `access_type`. Now edit `site_config.json` of your site (/frappe-bench/sites/your-site/) and add the following lines:
-`"dropbox_access_key": "app_key",` and
-`"dropbox_secret_key": "app_secret"`
Then you can go to the "Integrations" module and Allow Dropbox Access.
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