diff --git a/doc/Makefile.vc b/doc/Makefile.vc
index 60c7eee..1e783a0 100644
--- a/doc/Makefile.vc
+++ b/doc/Makefile.vc
@@ -62,7 +62,7 @@
 #
 
 install: 
-	copy calceph_c.pdf $(DESTDIR)\doc
-	copy calceph_fortran2003.pdf $(DESTDIR)\doc
-	copy calceph_fortran77.pdf $(DESTDIR)\doc
-	copy calceph_python.pdf $(DESTDIR)\doc
+	copy calceph_c.pdf "$(DESTDIR)"\doc
+	copy calceph_fortran2003.pdf "$(DESTDIR)"\doc
+	copy calceph_fortran77.pdf "$(DESTDIR)"\doc
+	copy calceph_python.pdf "$(DESTDIR)"\doc
diff --git a/mexapi/src/Makefile.vc b/mexapi/src/Makefile.vc
index 68e5d45..803c12f 100644
--- a/mexapi/src/Makefile.vc
+++ b/mexapi/src/Makefile.vc
@@ -62,10 +62,10 @@
 #
 
 install: 
-	copy interfacemex.c $(DESTDIR)\libexec\calceph\mex
-	copy CalcephBin.m $(DESTDIR)\libexec\calceph\mex
-	copy calceph_compilemex.m   $(DESTDIR)\libexec\calceph\mex
-	copy Constants.m $(DESTDIR)\libexec\calceph\mex
-	copy calceph_getversion_str.m $(DESTDIR)\libexec\calceph\mex
-	copy NaifId.m $(DESTDIR)\libexec\calceph\mex
-	copy calceph_seterrorhandler.m $(DESTDIR)\libexec\calceph\mex
+	copy interfacemex.c "$(DESTDIR)"\libexec\calceph\mex
+	copy CalcephBin.m "$(DESTDIR)"\libexec\calceph\mex
+	copy calceph_compilemex.m   "$(DESTDIR)"\libexec\calceph\mex
+	copy Constants.m "$(DESTDIR)"\libexec\calceph\mex
+	copy calceph_getversion_str.m "$(DESTDIR)"\libexec\calceph\mex
+	copy NaifId.m "$(DESTDIR)"\libexec\calceph\mex
+	copy calceph_seterrorhandler.m "$(DESTDIR)"\libexec\calceph\mex
diff --git a/src/Makefile.vc b/src/Makefile.vc
index 730b4a7..9e790b1 100644
--- a/src/Makefile.vc
+++ b/src/Makefile.vc
@@ -111,9 +111,9 @@ clean:
 # install target: "nmake /f Makefile.vc install DESTDIR=xxx" to perform the installation.
 #
 install: all $(F2003INSTALL)
-    copy f90calceph.h $(DESTDIR)\include
-    copy calceph.h $(DESTDIR)\include
-    copy $(LIBRARY) $(DESTDIR)\lib
+    copy f90calceph.h "$(DESTDIR)"\include
+    copy calceph.h "$(DESTDIR)"\include
+    copy $(LIBRARY) "$(DESTDIR)"\lib
 
 f2003install :
-    copy f2003calceph.mod $(DESTDIR)\include
+    copy f2003calceph.mod "$(DESTDIR)"\include