Windows 10 has officially been released to the public, but the server version of the OS, Windows Server 2016, is still in testing at Microsoft. The ISO files for Windows Server 2016 Technical Preview 3 have found there way onto pirate sites.
According to Neowin, the build number for the leaked version is 10514. Before the files were discovered, the Windows software leaked known as "WZor" posted up some screenshots of the build on his site. Microsoft is expected to release Windows Server 2016 Technical Preview 3 to Windows Insider testers sometime next week. The final version is scheduled to become available sometime in early 2016.