diff --git a/ostp-client/src/tunnel/linux_handler.rs b/ostp-client/src/tunnel/linux_handler.rs
index d257b7d..98822d4 100644
--- a/ostp-client/src/tunnel/linux_handler.rs
+++ b/ostp-client/src/tunnel/linux_handler.rs
@@ -18,7 +18,9 @@ pub async fn run_linux_tunnel(
         println!("[ostp-client] Starting Linux TUN handler initialization...");
     }
 
-    // 1. Locate tun2socks binary
+    // 1. Automatically ensure tun2socks binary is downloaded and present
+    super::download_tun2socks(debug)?;
+
     let exe = std::env::current_exe()?;
     let dir = exe.parent().ok_or_else(|| anyhow!("failed to get binary directory"))?;
     
diff --git a/ostp-client/src/tunnel/wintun_handler.rs b/ostp-client/src/tunnel/wintun_handler.rs
index 558438b..8c8a510 100644
--- a/ostp-client/src/tunnel/wintun_handler.rs
+++ b/ostp-client/src/tunnel/wintun_handler.rs
@@ -15,13 +15,16 @@ pub async fn run_wintun_tunnel(
         println!("[ostp-client] Initializing high-performance TUN tunnel via tun2socks...");
     }
 
-    // 1. Get executable directory to locate tun2socks.exe and wintun.dll
+    // 1. Automatically ensure Wintun and tun2socks dependencies are downloaded and present
+    super::download_wintun_dll(debug)?;
+    super::download_tun2socks(debug)?;
+
     let exe = std::env::current_exe()?;
     let dir = exe.parent().ok_or_else(|| anyhow!("failed to get binary directory"))?;
     let tun2socks_exe = dir.join("tun2socks.exe");
 
     if !tun2socks_exe.exists() {
-        return Err(anyhow!("tun2socks.exe not found! Please ensure initialization downloaded it successfully."));
+        return Err(anyhow!("tun2socks.exe not found! Even after download attempt, binary remains missing."));
     }
 
     // 2. Resolve Server IP for routing table exclusion