Index: trunk/src_plugins/export_stl/stl_models.c
===================================================================
--- trunk/src_plugins/export_stl/stl_models.c	(revision 35958)
+++ trunk/src_plugins/export_stl/stl_models.c	(revision 35959)
@@ -275,7 +275,8 @@
 		else
 			rnd_message(RND_MSG_ERROR, "STL model not found: %s\n", name);
 		free(full_path);
-		fclose(f);
+		if (f != NULL)
+			fclose(f);
 		htsp_set(models, rnd_strdup(name), head);
 	}
 	else