Like for 4.11 if you rebuild the solution you will encounter this error
/Epic was unexpected at this time
To solve this you need to open this batch file Engine/Build/BatchFiles/Rebuild.bat and add a “s” into every “%~dp0” like this:
@echo off
REM %1 is the game name
REM %2 is the platform name
REM %3 is the configuration name
IF EXIST "%~dps0\Clean.bat" (
call "%~dps0\Clean.bat" %*
) ELSE (
ECHO Clean.bat not found in %~dps0
EXIT /B 999
)
IF EXIST "%~dps0\Build.bat" (
call "%~dps0\Build.bat" %*
) ELSE (
ECHO Build.bat not found in %~dps0
EXIT /B 999
)
This has been fixed internally and should be included in a future release. Keep an eye on the announcements and releases sections of the forums for information of when this fix is released. In the mean time, thank you for the indication of how to solve the problem locally in case others have the same problem.
EDIT: I wanted to update you that this fix should be included by the final release of 4.12. Feel free to check the future preview builds and let us know if you are still having this problem after the final 4.12 release.