Some of the old software before 2010 may not be able to install/run normally on x64 or Windows 10 systems. Be aware of it before purchasing it.
Microsoft Dynamics CRM 2011 is available as a cloud offering or an on-premises installation by a partner/customer. As in CRM 4 these versions can be highly customized using advanced extensions. New feature set includes – Visualizations, Dashboards, Document Management, Grid Filters, Dialogs, Recurring Appointments, Custom Activities, Goal Management, Fetch based Reports, MAPI based Outlook clients, FLS etc.