If it ain't broke, don't fix it: That's the attitude that has kept Windows Server 2003 chugging along despite a number of new and improved offerings from Microsoft over the years. In fact, a recent survey from Spiceworks found that 53% of business are still running Windows Server 2003 —almost a year after the software's July 14, 2015 End of Life.
Microsoft offers a wide variety of their software and services through their TechNet Evaluation Center so that you can try them out before making a purchasing decision.
Some easy PowerShell to look for AD accounts that are not being used.
Microsoft plans to officially take the wraps off its next server version during it's mega-event in September.
Trying to activate an install of Windows on a client or server machine? Microsoft recently published a knowledge base article to help you resolve this issue.