Troubleshooting

See the following information for common troubleshooting for Netcode for GameObjects.

NullReferenceException when trying to start a server/host/client

Issue: When trying to start a server, host, or client by executing one of these lines of code:

NetworkManager.Singleton.StartServer()
NetworkManager.Singleton.StartHost()
NetworkManager.Singleton.StartClient()

The following exception is thrown:

NullReferenceException: Object reference not set to an instance of an object

Solution: You most likely forgot to add the NetworkManager component to a game object in your scene.

NullReferenceException when trying to send an RPC to the server

Issue: When the client tries to run InvokeServerRpc, the following exception is thrown:

NullReferenceException: Object reference not set to an instance of an object

Solution: You most likely forgot to Spawn() your object. Run Spawn() on your NetworkObject component as the server to fix this issue.

Server build is using 100% CPU

Issue: When running an MLAPI server created from a server build it has a cpu usage of 100% blocking all my other applications.

Solution: Unity server builds try to push as many Updates per second as possible. On a server this is most often not necessary. You can limit the target frame rate to reduce the amounts of Updates with this:

Application.targetFrameRate = 30;