--- a/ext/c4core/cmake/c4Project.cmake
+++ b/ext/c4core/cmake/c4Project.cmake
@@ -2643,4 +2643,4 @@
     set(_RUNTIME_INSTALL_DIR   bin/)
-    set(_ARCHIVE_INSTALL_DIR   lib/)
-    set(_LIBRARY_INSTALL_DIR   lib/) # TODO on Windows, ARCHIVE and LIBRARY dirs must be different to prevent name clashes
+    set(_ARCHIVE_INSTALL_DIR   lib/ CACHE STRING "")
+    set(_LIBRARY_INSTALL_DIR   lib/ CACHE STRING "")
     set(_INCLUDE_INSTALL_DIR   include/)