Ultimate++ Windows releases
Windows release a simple archive .7z archive. Unpack to directory of your preference, then just run theide.exe (or theide32.exe if you have 32-bit windows). U++ does not write anything to registry or outside its directory.
U++ comes in two variants:
upp-mingw contains TMD64 compiler system for out of the box operation
upp-win comes without compiler/SDK,
Both variants are able (on first install, when installation is moved or on demand - menu Setup/Instant setup) to detect and use SDK and C++ compiler from Microsoft Visual Studio 2015 (free community edition is fine). Note: While mingw/TDM64 is fine for light work, we really recommend using VS2015 C++ compiler for serious work. It significantly faster and better supported by 3rd party libraries.
When installing Visual Studio 2015, please make sure these options are checked
As can be seen on the above image, Visual C++ option from "Programming Languages" category is selected. Moreover, in "Windows and Web Development" Universal Windows App Development Tools is chosen.
TheIDE can also be configured to work with external MinGW or older Microsoft compilers and usually auto setup them (menu Setup/Legacy compilers automatic setup). However, as previous version of Visual C++ do not support parts of C++11 standard important for U++, we recommend using compiler from VS2015 (on the other hand, current U++ will work just fine in C++98 mode with previous Microsoft compiler).