diff --git a/src/core.c b/src/core.c
index db00fc66..0c3d7cbc 100644
--- a/src/core.c
+++ b/src/core.c
@@ -14877,10 +14877,8 @@ __cold static int env_close(MDBX_env *env) {
   }
 
 #if defined(_WIN32) || defined(_WIN64)
-  if (env->me_overlapped_fd) {
-    CloseHandle(env->me_overlapped_fd);
-    env->me_overlapped_fd = 0;
-  }
+  eASSERT(env, !env->me_overlapped_fd ||
+                   env->me_overlapped_fd == INVALID_HANDLE_VALUE);
   if (env->me_data_lock_event != INVALID_HANDLE_VALUE) {
     CloseHandle(env->me_data_lock_event);
     env->me_data_lock_event = INVALID_HANDLE_VALUE;
diff --git a/src/osal.c b/src/osal.c
index 69a0b49f..91276c66 100644
--- a/src/osal.c
+++ b/src/osal.c
@@ -1155,6 +1155,8 @@ MDBX_INTERNAL_FUNC void osal_ioring_destroy(osal_ioring_t *ior) {
   osal_memalign_free(ior->pool);
   osal_free(ior->event_pool);
   CloseHandle(ior->async_done);
+  if (ior->overlapped_fd)
+    CloseHandle(ior->overlapped_fd);
 #else
   osal_free(ior->pool);
 #endif