Cant compile c++

When I try to compile c++, I get a whole bunch of errors saying:

Error C2039 ‘toupper’: is not a member of ‘`global namespace’’ MyProject E:\Program Files (x86)\Epic Games\4.11\Engine\Source\Runtime\Core\Public\Misc\Char.h 145

All of the errors are about functions in the file Char.h. I have tried reinstalling ue4 and reinstalling visual studio, none of which helped. Im using windows 10. Any help is appreciated.

Can you show the code? Also show all errors (but copy them from output tab not that buggy VS error list everyone maniacally using :p)