If supported you can email your roster into your RosterBuster account. See below steps.
- When you have the roster in the inbox of the same email address you used during signup, press forward and send it to firstname.lastname@example.org
- The import will automatically start
- You receive an email stating if the roster has been successfully parsed or if there went something incorrect.
Also, the following articles might be relevant on this topic:
- Auto-forward email with the roster
- Add secondary sender email to your account
- Is emailing my roster supported?