mingw-w64 install

 At some point, the install program of mingw-w64 does not work properly with error message " The file is not downloaded properly." 

The solution to this problem is to directly download the compiled files. 

(1) Go to the link

https://sourceforge.net/projects/mingw-w64/files/

(2) Select the chosen version of files (I choose x86_64-posix-seh )

(3) download and unzip. copy the file to c:\mingw-w64 (or to any path of choice)

(4) include the path (/bin and /include) to the Windows. 

   (For example c:\mingw-w64\bin and c:\mingw-w64\include) 

    ("system property"->"advanced"->"environment variables"-> "Path"->"add") 

 (5) Now one can use mingw in the command prompt.