Build error for postmfix

[100%] Built target postmfix
Install the project…
– Install configuration: “RelWithDebInfo”
– Installing: C://libmfixsolver.dll.a
CMake Error at cmake_install.cmake:49 (file):
file INSTALL cannot copy file “C:/build/libmfixsolver.dll.a” to
“C://libmfixsolver.dll.a”: Permission denied.

Makefile:98: recipe for target ‘install’ failed
mingw32-make.exe: *** [install] Error 1

                 BUILD FAILED

I am getting this error while building Postmfix. Please Help!

What command are you using to build it?

Try
build_mfixsolver --postmfix