diff --git a/internal/setup.bat b/internal/setup.bat
index ece2105..d69879d 100644
--- a/internal/setup.bat
+++ b/internal/setup.bat
@@ -61,7 +61,7 @@ if "%BUILD_PYTHONLESS%" == "" goto pytorch else goto libtorch
 set VARIANT=shared-with-deps
 
 mkdir libtorch
-set "CMAKE_INSTALL_PREFIX=%CD%\libtorch"
+set "INSTALL_DIR=%CD%\libtorch"
 
 mkdir build
 pushd build