Emails are marked as spam when sent without the recipient's consent. The consent can be set via email opt-ins. Vtiger does not deliver emails to contacts with opt-in set to None, Opted out (user), or Opted out (contact). Email campaigns are delivered only to contacts with opt-in set to:
- Single opt-in (user)
- Single opt-in (webform)
- Double opt-in
To learn more about email consent,
click here.