diff --git a/vm/src/stdlib/os.rs b/vm/src/stdlib/os.rs
index 8eb1e3df7..ed3339265 100644
--- a/vm/src/stdlib/os.rs
+++ b/vm/src/stdlib/os.rs
@@ -141,6 +141,9 @@ pub fn os_open(
         }
     }
 
+    #[cfg(windows)]
+    let flags = flags & !(libc::O_WRONLY as u32);
+
     options.custom_flags(flags);
     let handle = options
         .open(fname.as_str())