diff --git a/Cargo.toml b/Cargo.toml
index 63578c8e..091e7d02 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -17,7 +17,7 @@ cfg-if = "1"
 futures-core = { version = "0.3", optional = true }
 libc = { version = "0.2", features = ["extra_traits"] }
 log = "0.4"
-thiserror = "1"
+thiserror = "2"
 tokio = { version = "1", features = [
     "net",
     "macros",
diff --git a/src/platform/windows/device.rs b/src/platform/windows/device.rs
index 8b80ef6c..4bad44d3 100644
--- a/src/platform/windows/device.rs
+++ b/src/platform/windows/device.rs
@@ -65,14 +65,14 @@ impl Device {
             if let Some(dns_servers) = &config.platform_config.dns_servers {
                 adapter.set_dns_servers(dns_servers)?;
             }
-            let mtu = config.mtu.unwrap_or(crate::DEFAULT_MTU);
-
+            if let Some(mtu) = config.mtu {
+                adapter.set_mtu(mtu as _)?;
+            }
             let capacity = config.ring_capacity.unwrap_or(MAX_RING_CAPACITY);
             let session = adapter.start_session(capacity)?;
-            adapter.set_mtu(mtu as _)?;
             let mut device = Device {
                 driver: Driver::Tun(Tun { session }),
-                mtu,
+                mtu: adapter.get_mtu()? as u16,
             };
 
             // This is not needed since we use netsh to set the address.