When a user fills out the name and email of a recipient/signer in the E-sign popup, you must select a sign type from the dropdown list. If you want to have a recipient sign the form, you must select Email To Sign, a.k.a ETS. Any other recipient that does not sign submits a SignType of "None". For example, if you are sending the form to 3 people, and you only want 2 of them to sign, you must enter their email addresses and set their SignType to ETS. The third recipient must not have an email address, and their SignType must be set to “None”, otherwise you will receive an error. To implement this process programmatically, use the GetDocusignResources method.
