It appears that Visual Studio Express 2012 only compiles 32 bit code.
That worked. Thanks.
I'll try VS2013 community edition.
Have you tried the Community Edition of VS 2013?
Try cygwin GCC for Windows, also Intel compiler is free for linux for non profit applications.
MinGV is listed as a tool for 64 targets, see CCompilerDriver/tutorial/SpecificCompilers for details.