http://blogs.msdn.com/dynamicscrmonline/archive/2009/07/03/auto-unsubscribe-in-crm-online.aspxIn Microsoft Dynamics CRM there is a feature to automatically set the Do Not Email flag for a contact if the click on an Unsubscribe link in a CRM generated email. In order to enable this functionality, navigate to Settings > Administration > Systemen-USCommunityServer 2.1 SP1 (Build: 61025.2)