diff --git a/Makefile.frag.w32 b/Makefile.frag.w32
index f1092f9..a8ac48b 100644
--- a/Makefile.frag.w32
+++ b/Makefile.frag.w32
@@ -34,5 +34,5 @@ test-awscrt: install $(AWSCRT_DIR)\src\api.h $(BUILD_DIR)\php_awscrt.dll
 	$(PHP_BINARY) -r "copy('https://getcomposer.org/installer', 'composer-setup.php');"
     $(PHP_BINARY) composer-setup.php
     $(PHP_BINARY) -r "unlink('composer-setup.php');"
-	$(PHP_BINARY) -c $(AWSCRT_DIR)\php-win.ini composer.phar --working-dir=$(AWSCRT_DIR) update
-	$(PHP_BINARY) -c $(AWSCRT_DIR)\php-win.ini composer.phar --working-dir=$(AWSCRT_DIR) run test-win
+	$(PHP_BINARY) -c $(AWSCRT_DIR)\php-win.ini .\composer.phar --working-dir=$(AWSCRT_DIR) update
+	$(PHP_BINARY) -c $(AWSCRT_DIR)\php-win.ini .\composer.phar --working-dir=$(AWSCRT_DIR) run test-win