This part has a problem. On windows if you download the tar.gz file, depending on how you unpack it, most of the time you will end up with files that may not run correctly like the two batch files in it... again the reason is that those files from the package have the Unix end-of-line encoding (LF) and will not work correctly used from windows console (cmd.com).
So either a conversion from Unix LF to Windows CR+LF on those files is needed, or just use mingw to compile it using "$ make -f Makefile.mingw init upnpc-static" from msys instead of Windows command prompt.