Windows VL editions: Vista, 7, 8, 8.1, 10, 11, Server 2008, 2008 R2, 2012,
2012 R2 also Office 2010, 2013, 2016.

Additionally, the program activates
Windows 8.1 Single Language;
Windows 8.1 Core;
Windows 8.1 Core N;
Windows 8.1 Pro WMC;
Windows Embedded 8.1 Industry Pro;
Windows Server 2012 R2 Standard;
Windows Server 2012 R2 Datacenter.

Run Activator.exe as administrator and follow on screen instructions and select your windows distribution and version.
Wait for it to activate.
Then Restart & Enjoy !

ReSharper Ultimate is a license that combines all individual JetBrains .NET tools, as well as ReSharper C++. Each ReSharper Ultimate license allows a single developer to use ReSharper, ReSharper C++, dotCover, dotTrace and dotMemory. If a single developer uses Visual Studio to code both in C# (or VB.NET, or TypeScript, or other languages supported by mainline ReSharper) and in C++, they would probably want to have ReSharper help them out in both worlds. Purchasing ReSharper and ReSharper C++ for this developer is a valid option but buying ReSharper Ultimate will actually cost you less than the two-license combo and will additionally make the developer eligible to use dotCover, dotTrace and dotMemory.