diff --git a/src/network/network_func.h b/src/network/network_func.h
--- a/src/network/network_func.h
+++ b/src/network/network_func.h
@@ -72,7 +72,6 @@ const char *GetClientIP(NetworkClientInf
 
 void NetworkServerDoMove(ClientID client_id, CompanyID company_id);
 void NetworkServerSendRcon(ClientID client_id, ConsoleColour colour_code, const char *string);
-void NetworkServerSendError(ClientID client_id, NetworkErrorCode error);
 void NetworkServerSendChat(NetworkAction action, DestType type, int dest, const char *msg, ClientID from_id, int64 data = 0);
 
 void NetworkServerKickClient(ClientID client_id);