diff --git a/boostregex/nppSpecifics.mak b/boostregex/nppSpecifics.mak
index e139f1514abd..62a2b39b02e4 100644
--- a/boostregex/nppSpecifics.mak
+++ b/boostregex/nppSpecifics.mak
@@ -19,8 +19,8 @@ CXXFLAGS=$(CXXFLAGS) -DSCI_OWNREGEX
 
 
 $(DIR_O)\UTF8DocumentIterator.obj:: ../../boostregex/UTF8DocumentIterator.cxx
-	$(CC) $(CXXFLAGS) -D_SILENCE_ALL_CXX17_DEPRECATION_WARNINGS -c -Fo$(DIR_O)\ %s
+	$(CC) $(CXXFLAGS) -D_SILENCE_ALL_CXX17_DEPRECATION_WARNINGS -c -Fo$@ %s
 	
 $(DIR_O)\BoostRegexSearch.obj:: ../../boostregex/BoostRegexSearch.cxx ../src/CharClassify.h ../src/RESearch.h	
-	$(CC) $(CXXFLAGS) -D_SILENCE_ALL_CXX17_DEPRECATION_WARNINGS -c -Fo$(DIR_O)\ %s
+	$(CC) $(CXXFLAGS) -D_SILENCE_ALL_CXX17_DEPRECATION_WARNINGS -c -Fo$@ %s