Solved SocketException: Error looking up error string

I have this error on update. Whats wrong?

Code:

(Filename: C:/buildslave/unity/build/artifacts/generated/common/runtime/UnityEngineDebugBindings.gen.cpp Line: 42)Loaded plugin Unity Core v1.0.3021 by Oxide Team(Filename: C:/buildslave/unity/build/artifacts/generated/common/runtime/UnityEngineDebugBindings.gen.cpp Line: 42)Loaded plugin Rust v1.0.3021 by Oxide Team(Filename: C:/buildslave/unity/build/artifacts/generated/common/runtime/UnityEngineDebugBindings.gen.cpp Line: 42)SocketException: Error looking up error string
  at System.Net.Sockets.Socket.Bind (System.Net.EndPoint local_end) [0x00000] in <filename unknown>:0
  at System.Net.Sockets.TcpListener.Start (Int32 backlog) [0x00000] in <filename unknown>:0
  at System.Net.Sockets.TcpListener.Start () [0x00000] in <filename unknown>:0
  at WebSocketSharp.Server.WebSocketServer.startReceiving () [0x00000] in <filename unknown>:0
  at WebSocketSharp.Server.WebSocketServer.Start () [0x00000] in <filename unknown>:0
  at Facepunch.Rcon.Listener.Start () [0x00000] in <filename unknown>:0
  at Facepunch.RCon.Initialize () [0x00000] in <filename unknown>:0
  at Bootstrap+<StartServer>c__IteratorF.MoveNext () [0x00000] in <filename unknown>:0
  at UnityEngine.SetupCoroutine.InvokeMoveNext (IEnumerator enumerator, IntPtr returnValueAddress) [0x00000] in <filename unknown>:0
UnityEngine.MonoBehaviour:StartCoroutine_Auto(IEnumerator)
UnityEngine.MonoBehaviour:StartCoroutine(IEnumerator)
<DedicatedServerStartup>c__IteratorE:MoveNext()
UnityEngine.SetupCoroutine:InvokeMoveNext(IEnumerator, IntPtr)(Filename:  Line: -1)

 

Sorry. Was my mistake. The port was used by another proccess.