The Sage CRM Developer Program website has recently changed and the address dpp.sagecrm.com is being discontinued.
The equivalent link on the new website is https://community.sagecrm.com/blogs/talking_about_customers/archive/2009/09/01/managing-employee-engagement-amp-crm-strategies-it-s-easier-than-you-think.aspx
Alternatively continue to the Sage CRM home page or the Sage CRM Partner Community home page.