When you create a New Project (from the main menu in Paratext 9 or the File menu in Paratext 8) you are given the option to register the project online. Project registration is only available to users who have been vetted by a Bible translation organization. Registered projects have additional features that are not available in Basic Tier projects as explained on the Registration page of this site.
When registering a project, Paratext requires an active Internet connection. It forwards you to a browser and you must sign in with the account you registered for Paratext with. Once the registration entry is complete, Paratext links the Paratext project with the entry in the registry.