diff --git a/Modules/FindEnvModules.cmake b/Modules/FindEnvModules.cmake
index a4ac0b47f3..dab97acc09 100644
--- a/Modules/FindEnvModules.cmake
+++ b/Modules/FindEnvModules.cmake
@@ -259,7 +259,7 @@ function(env_module_swap out_mod in_mod)
   )
 
   if(MOD_ARGS_OUTPUT_VARIABLE)
-    set(${MOD_ARGS_OUTPUT_VARIABLE} "${err_var}" PARENT_SCOPE)
+    set(${MOD_ARGS_OUTPUT_VARIABLE} "${tmp_out}" PARENT_SCOPE)
   endif()
   if(MOD_ARGS_RESULT_VARIABLE)
     set(${MOD_ARGS_RESULT_VARIABLE} ${tmp_ret} PARENT_SCOPE)