diff --git a/src/network/tun_win.rs b/src/network/tun_win.rs
index c35f9b6..b0dc997 100755
--- a/src/network/tun_win.rs
+++ b/src/network/tun_win.rs
@@ -789,6 +789,7 @@ pub fn del_route(net: &Ipv4Net, gw: &Ipv4Addr) -> Result<()> {
     let res = Command::new("route")
         .arg("delete")
         .arg(network)
+        .arg("MASK")
         .arg(mask)
         .arg(gw.to_string())
         .output()?;