Dropbox

To configure Dropbox, enter the Dropbox ID you want to allow access to.

All other Dropbox IDs will be blocked.

Dropbox Configuration

If a user tries to access the account with another unverified Dropbox ID, then a dropbox block page is shown.

If you need get further information from dropbox, you can get it here https://help.dropbox.com/teams-admins/admin/network-control.