[4.10] Failed to harvest environment variables

I’ve tried to create several c++ projects from Project Browser, but every time I get this error:

Running C:/Program Files (x86)/Epic Games/4.10/Engine/Binaries/DotNET/UnrealBuildTool.exe -projectfiles -project=“C:/Program Files (x86)/Epic Games/4.10/Templates/FP_FirstPerson/FP_FirstPerson.uproject” -game -rocket -progress
Discovering modules, targets and source code for game…
UnrealBuildTool Exception: ERROR: Failed to harvest environment variables

Changing templates or project path leads to the same error.
As suggested somewhere, I went to check my user/AppData/Local/Temp folder, seems I should have a .bat file which is not created. If I run EnvVarsToXML.exe from the command line (admin rights) I am able to produce a file containing environment variables, so I think this could be a problem involving UAC.
Using UE 4.10, VS 2015 sp1 on Windows 10

I managed to fix this by enabling “Run as Administrator” for the editor (also for Epic Games Launcher so I can start the engine from there).