diff --git a/prism/ext/ppl/Makefile b/prism/ext/ppl/Makefile
index ee4d4847..5f4e9100 100644
--- a/prism/ext/ppl/Makefile
+++ b/prism/ext/ppl/Makefile
@@ -34,14 +34,22 @@ libfiles: $(NATIVE_LIBS_COPY) $(COMMON_LIBS_COPY)
 
 ../../$(PRISM_LIB_DIR)/%: $(OSTYPE)/$(ARCH)/%
 	@if [ -f "$<" ]; then \
-	  echo cp -R $< $@; \
-	  cp -R $< $@; \
+	  echo Copying $< $@; \
+	  if [ $(OSTYPE) = "cywgin" ]; then \
+	    cp $< $@; \
+	  else \
+	    cp -R $< $@; \
+	  fi \
 	fi
 
 ../../$(PRISM_LIB_DIR)/%: common/%
 	@if [ -f "$<" ]; then \
-	  echo cp -R $< $@; \
-	  cp -R $< $@; \
+	  echo Copying $< $@; \
+	  if [ $(OSTYPE) = "cygwin" ]; then \
+	    cp $< $@; \
+	  else \
+	    cp -R $< $@; \
+	  fi \
 	fi
 
 clean: checks
diff --git a/prism/ext/yices/Makefile b/prism/ext/yices/Makefile
index 960d5230..812237a5 100644
--- a/prism/ext/yices/Makefile
+++ b/prism/ext/yices/Makefile
@@ -34,14 +34,22 @@ libfiles: $(NATIVE_LIBS_COPY) $(COMMON_LIBS_COPY)
 
 ../../$(PRISM_LIB_DIR)/%: $(OSTYPE)/$(ARCH)/%
 	@if [ -f "$<" ]; then \
-	  echo cp -R $< $@; \
-	  cp -R $< $@; \
+	  echo Copying $< $@; \
+	  if [ $(OSTYPE) = "cywgin" ]; then \
+	    cp $< $@; \
+	  else \
+	    cp -R $< $@; \
+	  fi \
 	fi
 
 ../../$(PRISM_LIB_DIR)/%: common/%
 	@if [ -f "$<" ]; then \
-	  echo cp -R $< $@; \
-	  cp -R $< $@; \
+	  echo Copying $< $@; \
+	  if [ $(OSTYPE) = "cygwin" ]; then \
+	    cp $< $@; \
+	  else \
+	    cp -R $< $@; \
+	  fi \
 	fi
 
 clean: checks
diff --git a/prism/ext/z3/Makefile b/prism/ext/z3/Makefile
index 8d604e85..d0317ffa 100644
--- a/prism/ext/z3/Makefile
+++ b/prism/ext/z3/Makefile
@@ -34,14 +34,22 @@ libfiles: $(NATIVE_LIBS_COPY) $(COMMON_LIBS_COPY)
 
 ../../$(PRISM_LIB_DIR)/%: $(OSTYPE)/$(ARCH)/%
 	@if [ -f "$<" ]; then \
-	  echo cp -R $< $@; \
-	  cp -R $< $@; \
+	  echo Copying $< $@; \
+	  if [ $(OSTYPE) = "cywgin" ]; then \
+	    cp $< $@; \
+	  else \
+	    cp -R $< $@; \
+	  fi \
 	fi
 
 ../../$(PRISM_LIB_DIR)/%: common/%
 	@if [ -f "$<" ]; then \
-	  echo cp -R $< $@; \
-	  cp -R $< $@; \
+	  echo Copying $< $@; \
+	  if [ $(OSTYPE) = "cygwin" ]; then \
+	    cp $< $@; \
+	  else \
+	    cp -R $< $@; \
+	  fi \
 	fi
 
 clean: checks