diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4f88f7c..adedccf 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -305,6 +305,7 @@ if(UNIX)
 	set(CPACK_STRIP_FILES breakhack)
 	set(CPACK_SOURCE_STRIP_FILES "")
 elseif(WIN32)
+	set(CPACK_NSIS_ENABLE_UNINSTALL_BEFORE_INSTALL ON)
 	set(CPACK_GENERATOR NSIS ZIP)
 endif()