diff --git a/com.unity.multiplayer.mlapi/Runtime/Serialization/NetworkWriter.cs b/com.unity.multiplayer.mlapi/Runtime/Serialization/NetworkWriter.cs
index 591b7b1940..ef160b1e8f 100644
--- a/com.unity.multiplayer.mlapi/Runtime/Serialization/NetworkWriter.cs
+++ b/com.unity.multiplayer.mlapi/Runtime/Serialization/NetworkWriter.cs
@@ -210,7 +210,7 @@ public void WriteObjectPacked(object value)
             {
                 if (!((NetworkObject)value).IsSpawned)
                 {
-                    throw new ArgumentException($"{nameof(NetworkWriter)} cannot write {nameof(NetworkObject)} types that are not spawned. {nameof(GameObject)}: {((GameObject)value).name}");
+                    throw new ArgumentException($"{nameof(NetworkWriter)} cannot write {nameof(NetworkObject)} types that are not spawned. {nameof(GameObject)}: {((NetworkObject)value).gameObject.name}");
                 }
 
                 WriteUInt64Packed(((NetworkObject)value).NetworkObjectId);
@@ -220,7 +220,7 @@ public void WriteObjectPacked(object value)
             {
                 if (!((NetworkBehaviour)value).HasNetworkObject || !((NetworkBehaviour)value).NetworkObject.IsSpawned)
                 {
-                    throw new ArgumentException($"{nameof(NetworkWriter)} cannot write {nameof(NetworkBehaviour)} types that are not spawned. {nameof(GameObject)}: {((GameObject)value).name}");
+                    throw new ArgumentException($"{nameof(NetworkWriter)} cannot write {nameof(NetworkBehaviour)} types that are not spawned. {nameof(GameObject)}: {((NetworkBehaviour)value).gameObject.name}");
                 }
 
                 WriteUInt64Packed(((NetworkBehaviour)value).NetworkObjectId);
diff --git a/com.unity.multiplayer.mlapi/Tests/Editor/NetworkSerializerTests.cs b/com.unity.multiplayer.mlapi/Tests/Editor/NetworkSerializerTests.cs
index d514ffbce4..88a14c153b 100644
--- a/com.unity.multiplayer.mlapi/Tests/Editor/NetworkSerializerTests.cs
+++ b/com.unity.multiplayer.mlapi/Tests/Editor/NetworkSerializerTests.cs
@@ -8,6 +8,29 @@ namespace MLAPI.EditorTests
 {
     public class NetworkSerializerTests
     {
+        [Test]
+        public void SerializeUnspawnedNetworkObject()
+        {
+            var gameObject = new GameObject(nameof(SerializeUnspawnedNetworkObject));
+            var networkObject = gameObject.AddComponent<NetworkObject>();
+
+            try
+            {
+                using (var outStream = PooledNetworkBuffer.Get())
+                using (var outWriter = PooledNetworkWriter.Get(outStream))
+                {
+                    outWriter.WriteObjectPacked(networkObject);
+                }
+
+                // we expect the exception below
+                Assert.Fail();
+            }
+            catch(ArgumentException exception)
+            {
+                Assert.True(exception.Message.IndexOf("NetworkWriter cannot write NetworkObject types that are not spawned") != -1);
+            }
+        }
+
         [Test]
         public void SerializeBool()
         {