Connect Client to Server from a Different project

Hello,

I have the follwing problem: I initialized a server on unity project 1 and connected a client from the same project. But now I want to connect a client from unity project 2, but when the this client tries to connect the server shuts down with the following error message: New incoming connection but not a server Afterwards the server shuts down. (If I try to connect the external client without having an exisiting client already connected it just doesn't connect without any error messages or shut downs.)

Server Code:

     private const string typeName = "ControllerConnection";
     private const string gameName = "Zodiac";
 
     void Awake()
     {
         StartServer ();
     }
     
     private void StartServer()
     {
         Network.InitializeServer (4, 25000, !Network.HavePublicAddress ());
         MasterServer.RegisterHost (typeName, gameName);
     }
     
     void OnServerInitialized()
     {
         Debug.Log ("Server Initialized");
     }

Client Code:

     private const string typeName = "ControllerConnection";
     private HostData[] hostList;
     private int movement = 0;
     
     void Start () {
         StartCoroutine (waitForIt ());
     }
     
     private void RefreshHostList()
     {
         MasterServer.RequestHostList (typeName);
         Debug.Log ("1. Requested Host List");
     }
     
     void OnMasterServerEvent(MasterServerEvent msEvent)
     {
         
         if (msEvent == MasterServerEvent.HostListReceived) 
         {
             Debug.Log("2. Startet to Join Server");
             hostList = MasterServer.PollHostList ();
             JoinServer(hostList[0]);
         }
     }
     
     private void JoinServer(HostData hostData)
     {
         Debug.Log ("3. Attempt to Connect");
         Network.Connect (hostData);
     }
     
     IEnumerator waitForIt()
     {
         yield return new WaitForSeconds (5);
         RefreshHostList();
     }
     
     void OnConnectedToServer()
     {
         Debug.Log ("4. Connected");
 
     }

I hope someone can help me out!! Thanks!